Kubernetes 管理员认证(CKA)考试笔记(二)
写在前面
- 嗯，准备考 cka证书，报了个班，花了好些钱，一定要考过去。
- 这篇博客是报班听课后整理的笔记，适合温习。
- 博文内容涉及
docker,k8s； - 写的有点多了，因为粘贴了代码，所以只能分开发布
- 本部分内容涉及
k8s多集群切换，k8s版本升级、etcd，pod相关 - 博文涉及镜像小伙伴有需要可以留言
生活的意义就是学着真实的活下去，生命的意义就是寻找生活的意义 -----山河已无恙
k8s多集群切换
创建一个新的集群,配置ssh免密,修改主机清单，然后使用之前的配置文件修改下
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$cat inventory[node]192.168.26.82192.168.26.83[master]192.168.26.81[temp]192.168.26.91192.168.26.92┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$cat init_c2_playbook.yml- name: init k8s hosts: temp tasks: # 关闭防火墙 - shell: firewall-cmd --set-default-zone=trusted # 关闭selinux - shell: getenforce register: out - debug: msg="{{out}}" - shell: setenforce 0 when: out.stdout != "Disabled" - replace: path: /etc/selinux/config regexp: "SELINUX=enforcing" replace: "SELINUX=disabled" - shell: cat /etc/selinux/config register: out - debug: msg="{{out}}" - copy: src: ./hosts_c2 dest: /etc/hosts force: yes # 关闭交换分区 - shell: swapoff -a - shell: sed -i '/swap/d' /etc/fstab - shell: cat /etc/fstab register: out - debug: msg="{{out}}" # 配置yum源 - shell: tar -cvf /etc/yum.tar /etc/yum.repos.d/ - shell: rm -rf /etc/yum.repos.d/* - shell: wget ftp://ftp.rhce.cc/k8s/* -P /etc/yum.repos.d/ # 安装docker-ce - yum: name: docker-ce state: present # 配置docker加速 - shell: mkdir /etc/docker - copy: src: ./daemon.json dest: /etc/docker/daemon.json - shell: systemctl daemon-reload - shell: systemctl restart docker # 配置属性，安装k8s相关包 - copy: src: ./k8s.conf dest: /etc/sysctl.d/k8s.conf - shell: yum install -y kubelet-1.21.1-0 kubeadm-1.21.1-0 kubectl-1.21.1-0 --disableexcludes=kubernetes # 缺少镜像导入 - copy: src: ./coredns-1.21.tar dest: /root/coredns-1.21.tar - shell: docker load -i /root/coredns-1.21.tar # 启动服务 - shell: systemctl restart kubelet - shell: systemctl enable kubelet┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$第二个集群，一个node节点，一个master节点
[root@vms91 ~]# kubectl get nodesNAME STATUS ROLES AGE VERSIONvms91.liruilongs.github.io Ready control-plane,master 139m v1.21.1vms92.liruilongs.github.io Ready <none> 131m v1.21.1[root@vms91 ~]# kubectl config viewapiVersion: v1clusters:- cluster: certificate-authority-data: DATA+OMITTED server: https://192.168.26.91:6443 name: kubernetescontexts:- context: cluster: kubernetes user: kubernetes-admin name: kubernetes-admin@kubernetescurrent-context: kubernetes-admin@kuberneteskind: Configpreferences: {}users:- name: kubernetes-admin user: client-certificate-data: REDACTED client-key-data: REDACTED[root@vms91 ~]#| 一个控制台管理多个集群，多集群切换： |
|---|
| 一个控制台管理多个集群 |
| 对于一个 kubeconfig文件来说，有3个部分： |
| cluster：集群信息 |
| context：属性–默认的命名空间 |
| user： 用户密匙 |
需要配置config,多个集群配置文件合并为一个
┌──[root@vms81.liruilongs.github.io]-[~/.kube]└─$pwd;ls/root/.kubecache configconfig
apiVersion: v1clusters:- cluster: certificate-authority-data: LS0.........0tCg== server: https://192.168.26.81:6443 name: cluster1- cluster: certificate-authority-data: LS0.........0tCg== server: https://192.168.26.91:6443 name: cluster2contexts:- context: cluster: cluster1 namespace: kube-public user: kubernetes-admin1 name: context1- context: cluster: cluster2 namespace: kube-system user: kubernetes-admin2 name: context2current-context: context2kind: Configpreferences: {}users:- name: kubernetes-admin1 user: client-certificate-data: LS0.......0tCg== client-key-data: LS0......LQo=- name: kubernetes-admin2 user: client-certificate-data: LS0.......0tCg== client-key-data: LS0......0tCg==多集群切换：kubectl config use-context context2
┌──[root@vms81.liruilongs.github.io]-[~/.kube]└─$kubectl config get-contextsCURRENT NAMECLUSTER AUTHINFO NAMESPACE* context1 cluster1 kubernetes-admin1 kube-public context2 cluster2 kubernetes-admin2 kube-system┌──[root@vms81.liruilongs.github.io]-[~/.kube]└─$kubectl get nodesNAME STATUS ROLES AGE VERSIONvms81.liruilongs.github.io Ready control-plane,master 23h v1.21.1vms82.liruilongs.github.io Ready <none> 23h v1.21.1vms83.liruilongs.github.io Ready <none> 23h v1.21.1┌──[root@vms81.liruilongs.github.io]-[~/.kube]└─$kubectl config use-context context2Switched to context "context2".┌──[root@vms81.liruilongs.github.io]-[~/.kube]└─$kubectl config get-contextsCURRENT NAMECLUSTER AUTHINFO NAMESPACE context1 cluster1 kubernetes-admin1 kube-public* context2 cluster2 kubernetes-admin2 kube-system┌──[root@vms81.liruilongs.github.io]-[~/.kube]└─$kubectl get nodesNAME STATUS ROLES AGE VERSIONvms91.liruilongs.github.io Ready control-plane,master 8h v1.21.1vms92.liruilongs.github.io Ready <none> 8h v1.21.1┌──[root@vms81.liruilongs.github.io]-[~/.kube]└─$三、ETCD
单节点ETCD
┌──[root@liruilongs.github.io]-[~]└─$ yum -y install etcd┌──[root@liruilongs.github.io]-[~]└─$ rpm -qc etcd/etc/etcd/etcd.conf┌──[root@liruilongs.github.io]-[~]└─$ vim $(rpm -qc etcd)┌──[root@liruilongs.github.io]-[~]└─$#[Member]# 数据位置ETCD_DATA_DIR="/var/lib/etcd/default.etcd" # 数据同步端口ETCD_LISTEN_PEER_URLS="http://192.168.26.91:2380,http://localhost:2380" # 读写端口ETCD_LISTEN_CLIENT_URLS="http://192.168.26.91:2379,http://localhost:2379" ETCD_NAME="default" #[Clustering]ETCD_ADVERTISE_CLIENT_URLS="http://localhost:2379"┌──[root@liruilongs.github.io]-[~]└─$ systemctl enable etcd --now┌──[root@liruilongs.github.io]-[~]└─$ etcdctl member list8e9e05c52164694d: name=default peerURLs=http://localhost:2380 clientURLs=http://localhost:2379 isLeader=true┌──[root@liruilongs.github.io]-[~]└─$ etcdctl cluster-healthmember 8e9e05c52164694d is healthy: got healthy result from http://localhost:2379cluster is healthy┌──[root@liruilongs.github.io]-[~]└─$ etcdctl ls /┌──[root@liruilongs.github.io]-[~]└─$ etcdctl mkdir cka┌──[root@liruilongs.github.io]-[~]└─$ etcdctl ls //cka┌──[root@liruilongs.github.io]-[~]└─$ etcdctl rmdir /cka┌──[root@liruilongs.github.io]-[~]└─$ etcdctl ls /┌──[root@liruilongs.github.io]-[~]└─$2和3版本切换
┌──[root@liruilongs.github.io]-[~]└─$ etcdctl -vetcdctl version: 3.3.11API version: 2┌──[root@liruilongs.github.io]-[~]└─$ export ETCDCTL_API=3┌──[root@liruilongs.github.io]-[~]└─$ etcdctl versionetcdctl version: 3.3.11API version: 3.3┌──[root@liruilongs.github.io]-[~]└─$etcd集群构建
- ETCD集群是一个分布式系统,使用Raft协议来维护集群内各个节点状态的一致性。
- 主机状态 Leader, Follower, Candidate
- 当集群初始化时候，每个节点都是Follower角色，通过心跳与其他节点同步数据
- 当Follower在一定时间内没有收到来自主节点的心跳，会将自己角色改变为Candidate，并发起一次选主投票
- 配置etcd集群，建议尽可能是奇数个节点，而不要偶数个节点
创建集群
环境准备
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$cat inventory......[etcd]192.168.26.100192.168.26.101192.168.26.102┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible etcd -m ping192.168.26.100 | SUCCESS => { "ansible_facts": { "discovered_interpreter_python": "/usr/bin/python" }, "changed": false, "ping": "pong"}192.168.26.102 | SUCCESS => { "ansible_facts": { "discovered_interpreter_python": "/usr/bin/python" }, "changed": false, "ping": "pong"}192.168.26.101 | SUCCESS => { "ansible_facts": { "discovered_interpreter_python": "/usr/bin/python" }, "changed": false, "ping": "pong"}┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible etcd -m yum -a "name=etcd state=installed"配置文件修改
这里用前两台(192.168.26.100,192.168.26.101)初始化集群，第三台(192.168.26.102 )以添加的方式加入集群
本机编写配置文件。
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$cat etcd.confETCD_DATA_DIR="/var/lib/etcd/cluster.etcd"ETCD_LISTEN_PEER_URLS="http://192.168.26.100:2380,http://localhost:2380"ETCD_LISTEN_CLIENT_URLS="http://192.168.26.100:2379,http://localhost:2379"ETCD_NAME="etcd-100"ETCD_INITIAL_ADVERTISE_PEER_URLS="http://192.168.26.100:2380"ETCD_ADVERTISE_CLIENT_URLS="http://localhost:2379,http://192.168.26.100:2379"ETCD_INITIAL_CLUSTER="etcd-100=http://192.168.26.100:2380,etcd-101=http://192.168.26.101:2380"ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"ETCD_INITIAL_CLUSTER_STATE="new"把配置文件拷贝到192.168.26.100,192.168.26.101
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.100,192.168.26.101 -m copy -a "src=./etcd.conf dest=/etc/etcd/etcd.conf force=yes"192.168.26.101 | CHANGED => { "ansible_facts": { "discovered_interpreter_python": "/usr/bin/python" }, "changed": true, "checksum": "bae3b8bc6636bf7304cce647b7068aa45ced859b", "dest": "/etc/etcd/etcd.conf", "gid": 0, "group": "root", "md5sum": "5f2a3fbe27515f85b7f9ed42a206c2a6", "mode": "0644", "owner": "root", "size": 533, "src": "/root/.ansible/tmp/ansible-tmp-1633800905.88-59602-39965601417441/source", "state": "file", "uid": 0}192.168.26.100 | CHANGED => { "ansible_facts": { "discovered_interpreter_python": "/usr/bin/python" }, "changed": true, "checksum": "bae3b8bc6636bf7304cce647b7068aa45ced859b", "dest": "/etc/etcd/etcd.conf", "gid": 0, "group": "root", "md5sum": "5f2a3fbe27515f85b7f9ed42a206c2a6", "mode": "0644", "owner": "root", "size": 533, "src": "/root/.ansible/tmp/ansible-tmp-1633800905.9-59600-209338664801782/source", "state": "file", "uid": 0}检查配置文件
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.100,192.168.26.101 -m shell -a "cat /etc/etcd/etcd.conf"192.168.26.101 | CHANGED | rc=0 >>ETCD_DATA_DIR="/var/lib/etcd/cluster.etcd"ETCD_LISTEN_PEER_URLS="http://192.168.26.100:2380,http://localhost:2380"ETCD_LISTEN_CLIENT_URLS="http://192.168.26.100:2379,http://localhost:2379"ETCD_NAME="etcd-100"ETCD_INITIAL_ADVERTISE_PEER_URLS="http://192.168.26.100:2380"ETCD_ADVERTISE_CLIENT_URLS="http://localhost:2379,http://192.168.26.100:2379"ETCD_INITIAL_CLUSTER="etcd-100=http://192.168.26.100:2380,etcd-101=http://192.168.26.101:2380"ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"ETCD_INITIAL_CLUSTER_STATE="new"192.168.26.100 | CHANGED | rc=0 >>ETCD_DATA_DIR="/var/lib/etcd/cluster.etcd"ETCD_LISTEN_PEER_URLS="http://192.168.26.100:2380,http://localhost:2380"ETCD_LISTEN_CLIENT_URLS="http://192.168.26.100:2379,http://localhost:2379"ETCD_NAME="etcd-100"ETCD_INITIAL_ADVERTISE_PEER_URLS="http://192.168.26.100:2380"ETCD_ADVERTISE_CLIENT_URLS="http://localhost:2379,http://192.168.26.100:2379"ETCD_INITIAL_CLUSTER="etcd-100=http://192.168.26.100:2380,etcd-101=http://192.168.26.101:2380"ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"ETCD_INITIAL_CLUSTER_STATE="new"修改101的配置文件
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.101 -m shell -a "sed -i '1,9s/100/101/g' /etc/etcd/etcd.conf"192.168.26.101 | CHANGED | rc=0 >>┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.100,192.168.26.101 -m shell -a "cat -n /etc/etcd/etcd.conf"192.168.26.100 | CHANGED | rc=0 >> 1 ETCD_DATA_DIR="/var/lib/etcd/cluster.etcd" 2 3 ETCD_LISTEN_PEER_URLS="http://192.168.26.100:2380,http://localhost:2380" 4 ETCD_LISTEN_CLIENT_URLS="http://192.168.26.100:2379,http://localhost:2379" 5 6 ETCD_NAME="etcd-100" 7 ETCD_INITIAL_ADVERTISE_PEER_URLS="http://192.168.26.100:2380" 8 9 ETCD_ADVERTISE_CLIENT_URLS="http://localhost:2379,http://192.168.26.100:2379" 10 11 ETCD_INITIAL_CLUSTER="etcd-100=http://192.168.26.100:2380,etcd-101=http://192.168.26.101:2380" 12 ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster" 13 ETCD_INITIAL_CLUSTER_STATE="new"192.168.26.101 | CHANGED | rc=0 >> 1 ETCD_DATA_DIR="/var/lib/etcd/cluster.etcd" 2 3 ETCD_LISTEN_PEER_URLS="http://192.168.26.101:2380,http://localhost:2380" 4 ETCD_LISTEN_CLIENT_URLS="http://192.168.26.101:2379,http://localhost:2379" 5 6 ETCD_NAME="etcd-101" 7 ETCD_INITIAL_ADVERTISE_PEER_URLS="http://192.168.26.101:2380" 8 9 ETCD_ADVERTISE_CLIENT_URLS="http://localhost:2379,http://192.168.26.101:2379" 10 11 ETCD_INITIAL_CLUSTER="etcd-100=http://192.168.26.100:2380,etcd-101=http://192.168.26.101:2380" 12 ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster" 13 ETCD_INITIAL_CLUSTER_STATE="new"┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$查看etcd集群
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.100,192.168.26.101 -m shell -a "etcdctl member list"192.168.26.100 | CHANGED | rc=0 >>6f2038a018db1103: name=etcd-100 peerURLs=http://192.168.26.100:2380 clientURLs=http://192.168.26.100:2379,http://localhost:2379 isLeader=falsebd330576bb637f25: name=etcd-101 peerURLs=http://192.168.26.101:2380 clientURLs=http://192.168.26.101:2379,http://localhost:2379 isLeader=true192.168.26.101 | CHANGED | rc=0 >>6f2038a018db1103: name=etcd-100 peerURLs=http://192.168.26.100:2380 clientURLs=http://192.168.26.100:2379,http://localhost:2379 isLeader=falsebd330576bb637f25: name=etcd-101 peerURLs=http://192.168.26.101:2380 clientURLs=http://192.168.26.101:2379,http://localhost:2379 isLeader=true┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$添加etcd 192.168.26.102
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.100 -m shell -a "etcdctl member add etcd-102 http://192.168.26.102:2380"192.168.26.100 | CHANGED | rc=0 >>Added member named etcd-102 with ID 2fd4f9ba70a04579 to clusterETCD_NAME="etcd-102"ETCD_INITIAL_CLUSTER="etcd-102=http://192.168.26.102:2380,etcd-100=http://192.168.26.100:2380,etcd-101=http://192.168.26.101:2380"ETCD_INITIAL_CLUSTER_STATE="existing"┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$修改之前写好的配置文件给102
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$sed -i '1,8s/100/102/g' etcd.conf┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$sed -i '13s/new/existing/' etcd.conf┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$sed -i 's#ETCD_INITIAL_CLUSTER="#ETCD_INITIAL_CLUSTER="etcd-102=http://192.168.26.102:2380,#' etcd.conf┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$cat -n etcd.conf 1 ETCD_DATA_DIR="/var/lib/etcd/cluster.etcd" 2 3 ETCD_LISTEN_PEER_URLS="http://192.168.26.102:2380,http://localhost:2380" 4 ETCD_LISTEN_CLIENT_URLS="http://192.168.26.102:2379,http://localhost:2379" 5 6 ETCD_NAME="etcd-102" 7 ETCD_INITIAL_ADVERTISE_PEER_URLS="http://192.168.26.102:2380" 8 9 ETCD_ADVERTISE_CLIENT_URLS="http://localhost:2379,http://192.168.26.100:2379" 10 11 ETCD_INITIAL_CLUSTER="etcd-102=http://192.168.26.102:2380,etcd-100=http://192.168.26.100:2380,etcd-101=http://192.168.26.101:2380" 12 ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster" 13 ETCD_INITIAL_CLUSTER_STATE="existing"┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$配置文件拷贝替换，启动etcd
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.102 -m copy -a "src=./etcd.conf dest=/etc/etcd/etcd.conf force=yes"192.168.26.102 | CHANGED => { "ansible_facts": { "discovered_interpreter_python": "/usr/bin/python" }, "changed": true, "checksum": "2d8fa163150e32da563f5e591134b38cc356d237", "dest": "/etc/etcd/etcd.conf", "gid": 0, "group": "root", "md5sum": "389c2850d434478e2d4d57a7798196de", "mode": "0644", "owner": "root", "size": 574, "src": "/root/.ansible/tmp/ansible-tmp-1633803533.57-102177-227527368141930/source", "state": "file", "uid": 0}┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.102 -m shell -a "systemctl enable etcd --now"192.168.26.102 | CHANGED | rc=0 >>Created symlink from /etc/systemd/system/multi-user.target.wants/etcd.service to /usr/lib/systemd/system/etcd.service.┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$检查集群是否添加成功
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible etcd -m shell -a "etcdctl member list"192.168.26.101 | CHANGED | rc=0 >>2fd4f9ba70a04579: name=etcd-102 peerURLs=http://192.168.26.102:2380 clientURLs=http://192.168.26.100:2379,http://localhost:2379 isLeader=false6f2038a018db1103: name=etcd-100 peerURLs=http://192.168.26.100:2380 clientURLs=http://192.168.26.100:2379,http://localhost:2379 isLeader=falsebd330576bb637f25: name=etcd-101 peerURLs=http://192.168.26.101:2380 clientURLs=http://192.168.26.101:2379,http://localhost:2379 isLeader=true192.168.26.102 | CHANGED | rc=0 >>2fd4f9ba70a04579: name=etcd-102 peerURLs=http://192.168.26.102:2380 clientURLs=http://192.168.26.100:2379,http://localhost:2379 isLeader=false6f2038a018db1103: name=etcd-100 peerURLs=http://192.168.26.100:2380 clientURLs=http://192.168.26.100:2379,http://localhost:2379 isLeader=falsebd330576bb637f25: name=etcd-101 peerURLs=http://192.168.26.101:2380 clientURLs=http://192.168.26.101:2379,http://localhost:2379 isLeader=true192.168.26.100 | CHANGED | rc=0 >>2fd4f9ba70a04579: name=etcd-102 peerURLs=http://192.168.26.102:2380 clientURLs=http://192.168.26.100:2379,http://localhost:2379 isLeader=false6f2038a018db1103: name=etcd-100 peerURLs=http://192.168.26.100:2380 clientURLs=http://192.168.26.100:2379,http://localhost:2379 isLeader=falsebd330576bb637f25: name=etcd-101 peerURLs=http://192.168.26.101:2380 clientURLs=http://192.168.26.101:2379,http://localhost:2379 isLeader=true┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$设置环境变量，这里有一点麻烦。
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible etcd -m shell -a "echo 'export ETCDCTL_API=3' >> ~/.bashrc"192.168.26.100 | CHANGED | rc=0 >>192.168.26.102 | CHANGED | rc=0 >>192.168.26.101 | CHANGED | rc=0 >>┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible etcd -m shell -a "cat ~/.bashrc"192.168.26.100 | CHANGED | rc=0 >># .bashrc# User specific aliases and functionsalias rm='rm -i'alias cp='cp -i'alias mv='mv -i'# Source global definitionsif [ -f /etc/bashrc ]; then . /etc/bashrcfiexport ETCDCTL_API=3192.168.26.102 | CHANGED | rc=0 >># .bashrc# User specific aliases and functionsalias rm='rm -i'alias cp='cp -i'alias mv='mv -i'# Source global definitionsif [ -f /etc/bashrc ]; then . /etc/bashrcfiexport ETCDCTL_API=3192.168.26.101 | CHANGED | rc=0 >># .bashrc# User specific aliases and functionsalias rm='rm -i'alias cp='cp -i'alias mv='mv -i'# Source global definitionsif [ -f /etc/bashrc ]; then . /etc/bashrcfiexport ETCDCTL_API=3┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible etcd -m shell -a "etcdctl version"192.168.26.100 | CHANGED | rc=0 >>etcdctl version: 3.3.11API version: 3.3192.168.26.102 | CHANGED | rc=0 >>etcdctl version: 3.3.11API version: 3.3192.168.26.101 | CHANGED | rc=0 >>etcdctl version: 3.3.11API version: 3.3┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$同步性测试
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$# 同步性测试┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.100 -a "etcdctl put name liruilong"192.168.26.100 | CHANGED | rc=0 >>OK┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible etcd -a "etcdctl get name"192.168.26.100 | CHANGED | rc=0 >>nameliruilong192.168.26.101 | CHANGED | rc=0 >>nameliruilong192.168.26.102 | CHANGED | rc=0 >>nameliruilong┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$etcd集群备份，恢复
准备数据
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.100 -a "etcdctl put name liruilong"192.168.26.100 | CHANGED | rc=0 >>OK┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible etcd -a "etcdctl get name"192.168.26.102 | CHANGED | rc=0 >>nameliruilong192.168.26.100 | CHANGED | rc=0 >>nameliruilong192.168.26.101 | CHANGED | rc=0 >>nameliruilong在任何一台主机上对 etcd 做快照
#在任何一台主机上对 etcd 做快照┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.101 -a "etcdctl snapshot save snap20211010.db"192.168.26.101 | CHANGED | rc=0 >>Snapshot saved at snap20211010.db┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$# 此快照里包含了刚刚写的数据 name=liruilong，然后把快照文件到所有节点┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.101 -a "scp /root/snap20211010.db root@192.168.26.100:/root/"192.168.26.101 | CHANGED | rc=0 >>┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.101 -a "scp /root/snap20211010.db root@192.168.26.102:/root/"192.168.26.101 | CHANGED | rc=0 >>┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$清空数据
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible etcd -a "etcdctl del name"192.168.26.101 | CHANGED | rc=0 >>1192.168.26.102 | CHANGED | rc=0 >>0192.168.26.100 | CHANGED | rc=0 >>0┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$在所有节点上关闭 etcd，并删除/var/lib/etcd/里所有数据：
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$# 在所有节点上关闭 etcd，并删除/var/lib/etcd/里所有数据：┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible etcd -a "systemctl stop etcd"192.168.26.100 | CHANGED | rc=0 >>192.168.26.102 | CHANGED | rc=0 >>192.168.26.101 | CHANGED | rc=0 >>┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible etcd -m shell -a "rm -rf /var/lib/etcd/*"[WARNING]: Consider using the file module with state=absent rather than running 'rm'. If you need touse command because file is insufficient you can add 'warn: false' to this command task or set'command_warnings=False' in ansible.cfg to get rid of this message.192.168.26.102 | CHANGED | rc=0 >>192.168.26.100 | CHANGED | rc=0 >>192.168.26.101 | CHANGED | rc=0 >>在所有节点上把快照文件的所有者和所属组设置为 etcd：
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible etcd -a "chown etcd.etcd /root/snap20211010.db"[WARNING]: Consider using the file module with owner rather than running 'chown'. If you need to usecommand because file is insufficient you can add 'warn: false' to this command task or set'command_warnings=False' in ansible.cfg to get rid of this message.192.168.26.100 | CHANGED | rc=0 >>192.168.26.102 | CHANGED | rc=0 >>192.168.26.101 | CHANGED | rc=0 >>┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$# 在每台节点上开始恢复数据：在每台节点上开始恢复数据：
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.100 -m script -a "./snapshot_restore.sh"192.168.26.100 | CHANGED => { "changed": true, "rc": 0, "stderr": "Shared connection to 192.168.26.100 closed.\r\n", "stderr_lines": [ "Shared connection to 192.168.26.100 closed." ], "stdout": "2021-10-10 12:14:30.726021 I | etcdserver/membership: added member 6f2038a018db1103 [http://192.168.26.100:2380] to cluster af623437f584d792\r\n2021-10-10 12:14:30.726234 I | etcdserver/membership: added member bd330576bb637f25 [http://192.168.26.101:2380] to cluster af623437f584d792\r\n", "stdout_lines": [ "2021-10-10 12:14:30.726021 I | etcdserver/membership: added member 6f2038a018db1103 [http://192.168.26.100:2380] to cluster af623437f584d792", "2021-10-10 12:14:30.726234 I | etcdserver/membership: added member bd330576bb637f25 [http://192.168.26.101:2380] to cluster af623437f584d792" ]}┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$cat -n ./snapshot_restore.sh 1 #!/bin/bash 2 3 # 每台节点恢复镜像 4 5 etcdctl snapshot restore /root/snap20211010.db \ 6 --name etcd-100 \ 7 --initial-advertise-peer-urls="http://192.168.26.100:2380" \ 8 --initial-cluster="etcd-100=http://192.168.26.100:2380,etcd-101=http://192.168.26.101:2380" \ 9 --data-dir="/var/lib/etcd/cluster.etcd" 10┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$sed '6,7s/100/101/g' ./snapshot_restore.sh#!/bin/bash# 每台节点恢复镜像etcdctl snapshot restore /root/snap20211010.db \--name etcd-101 \--initial-advertise-peer-urls="http://192.168.26.101:2380" \--initial-cluster="etcd-100=http://192.168.26.100:2380,etcd-101=http://192.168.26.101:2380" \--data-dir="/var/lib/etcd/cluster.etcd"┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$sed -i '6,7s/100/101/g' ./snapshot_restore.sh┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$cat ./snapshot_restore.sh#!/bin/bash# 每台节点恢复镜像etcdctl snapshot restore /root/snap20211010.db \--name etcd-101 \--initial-advertise-peer-urls="http://192.168.26.101:2380" \--initial-cluster="etcd-100=http://192.168.26.100:2380,etcd-101=http://192.168.26.101:2380" \--data-dir="/var/lib/etcd/cluster.etcd"┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.101 -m script -a "./snapshot_restore.sh"192.168.26.101 | CHANGED => { "changed": true, "rc": 0, "stderr": "Shared connection to 192.168.26.101 closed.\r\n", "stderr_lines": [ "Shared connection to 192.168.26.101 closed." ], "stdout": "2021-10-10 12:20:26.032754 I | etcdserver/membership: added member 6f2038a018db1103 [http://192.168.26.100:2380] to cluster af623437f584d792\r\n2021-10-10 12:20:26.032930 I | etcdserver/membership: added member bd330576bb637f25 [http://192.168.26.101:2380] to cluster af623437f584d792\r\n", "stdout_lines": [ "2021-10-10 12:20:26.032754 I | etcdserver/membership: added member 6f2038a018db1103 [http://192.168.26.100:2380] to cluster af623437f584d792", "2021-10-10 12:20:26.032930 I | etcdserver/membership: added member bd330576bb637f25 [http://192.168.26.101:2380] to cluster af623437f584d792" ]}┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$所有节点把/var/lib/etcd 及里面内容的所有者和所属组改为 etcd：v然后分别启动 etcd
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible etcd -a "chown -R etcd.etcd /var/lib/etcd/"[WARNING]: Consider using the file module with owner rather than running 'chown'. If you need to usecommand because file is insufficient you can add 'warn: false' to this command task or set'command_warnings=False' in ansible.cfg to get rid of this message.192.168.26.100 | CHANGED | rc=0 >>192.168.26.101 | CHANGED | rc=0 >>192.168.26.102 | CHANGED | rc=0 >>┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible etcd -a "systemctl start etcd"192.168.26.102 | FAILED | rc=1 >>Job for etcd.service failed because the control process exited with error code. See "systemctl status etcd.service" and "journalctl -xe" for details.non-zero return code192.168.26.101 | CHANGED | rc=0 >>192.168.26.100 | CHANGED | rc=0 >>┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$把剩下的节点添加进集群
# etcdctl member add etcd_name –peer-urls=”https://peerURLs”[root@vms100 cluster.etcd]# etcdctl member add etcd-102 --peer-urls="http://192.168.26.102:2380"Member fbd8a96cbf1c004d added to cluster af623437f584d792ETCD_NAME="etcd-102"ETCD_INITIAL_CLUSTER="etcd-100=http://192.168.26.100:2380,etcd-101=http://192.168.26.101:2380,etcd-102=http://192.168.26.102:2380"ETCD_INITIAL_ADVERTISE_PEER_URLS="http://192.168.26.102:2380"ETCD_INITIAL_CLUSTER_STATE="existing"[root@vms100 cluster.etcd]#测试恢复结果
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.102 -m copy -a "src=./etcd.conf dest=/etc/etcd/etcd.conf force=yes"192.168.26.102 | SUCCESS => { "ansible_facts": { "discovered_interpreter_python": "/usr/bin/python" }, "changed": false, "checksum": "2d8fa163150e32da563f5e591134b38cc356d237", "dest": "/etc/etcd/etcd.conf", "gid": 0, "group": "root", "mode": "0644", "owner": "root", "path": "/etc/etcd/etcd.conf", "size": 574, "state": "file", "uid": 0}┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.102 -m shell -a "systemctl enable etcd --now"192.168.26.102 | CHANGED | rc=0 >>┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible etcd -m shell -a "etcdctl member list"192.168.26.101 | CHANGED | rc=0 >>6f2038a018db1103, started, etcd-100, http://192.168.26.100:2380, http://192.168.26.100:2379,http://localhost:2379bd330576bb637f25, started, etcd-101, http://192.168.26.101:2380, http://192.168.26.101:2379,http://localhost:2379fbd8a96cbf1c004d, started, etcd-102, http://192.168.26.102:2380, http://192.168.26.100:2379,http://localhost:2379192.168.26.100 | CHANGED | rc=0 >>6f2038a018db1103, started, etcd-100, http://192.168.26.100:2380, http://192.168.26.100:2379,http://localhost:2379bd330576bb637f25, started, etcd-101, http://192.168.26.101:2380, http://192.168.26.101:2379,http://localhost:2379fbd8a96cbf1c004d, started, etcd-102, http://192.168.26.102:2380, http://192.168.26.100:2379,http://localhost:2379192.168.26.102 | CHANGED | rc=0 >>6f2038a018db1103, started, etcd-100, http://192.168.26.100:2380, http://192.168.26.100:2379,http://localhost:2379bd330576bb637f25, started, etcd-101, http://192.168.26.101:2380, http://192.168.26.101:2379,http://localhost:2379fbd8a96cbf1c004d, started, etcd-102, http://192.168.26.102:2380, http://192.168.26.100:2379,http://localhost:2379┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible etcd -a "etcdctl get name"192.168.26.102 | CHANGED | rc=0 >>nameliruilong192.168.26.101 | CHANGED | rc=0 >>nameliruilong192.168.26.100 | CHANGED | rc=0 >>nameliruilong┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$k8s中etcd以pod的方式设置
┌──[root@vms81.liruilongs.github.io]-[~]└─$kubectl get podsNAMEREADY STATUS RESTARTS AGEcalico-kube-controllers-78d6f96c7b-79xx4 1/1 Running57 3d1hcalico-node-ntm7v 1/1 Running16 3d11hcalico-node-skzjp 0/1 Running42 3d11hcalico-node-v7pj5 1/1 Running9 3d11hcoredns-545d6fc579-9h2z4 1/1 Running9 3d1hcoredns-545d6fc579-xgn8x 1/1 Running10 3d1hetcd-vms81.liruilongs.github.io 1/1 Running8 3d11hkube-apiserver-vms81.liruilongs.github.io 1/1 Running20 3d11hkube-controller-manager-vms81.liruilongs.github.io 1/1 Running26 3d11hkube-proxy-rbhgf 1/1 Running4 3d11hkube-proxy-vm2sf 1/1 Running3 3d11hkube-proxy-zzbh9 1/1 Running2 3d11hkube-scheduler-vms81.liruilongs.github.io 1/1 Running24 3d11hmetrics-server-bcfb98c76-6q5mb 1/1 Terminating 0 43hmetrics-server-bcfb98c76-9ptf4 1/1 Terminating 0 27hmetrics-server-bcfb98c76-bbr6n 0/1 Pending0 12h┌──[root@vms81.liruilongs.github.io]-[~]└─$四、升级K8S
不能跨版本更新
| 升级工作的基本流程如下 |
|---|
| 升级主控制平面节点 |
| 升级工作节点 |
确定要升级到哪个版本
┌──[root@vms81.liruilongs.github.io]-[~]└─$yum list --showduplicates kubeadm --disableexcludes=kubernetes# 在列表中查找最新的 1.22 版本# 它看起来应该是 1.22.x-0，其中 x 是最新的补丁版本现有环境
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl get nodesNAME STATUS ROLES AGE VERSIONvms81.liruilongs.github.io NotReady control-plane,master 11m v1.21.1vms82.liruilongs.github.io NotReady <none> 12s v1.21.1vms83.liruilongs.github.io NotReady <none> 11s v1.21.1┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$升级master
控制面节点上的升级过程应该每次处理一个节点。 首先选择一个要先行升级的控制面节点。该节点上必须拥有 /etc/kubernetes/admin.conf 文件。
执行 “kubeadm upgrade”
升级 kubeadm：
# 用最新的补丁版本号替换 1.22.x-0 中的 x┌──[root@vms81.liruilongs.github.io]-[~]└─$yum install -y kubeadm-1.22.2-0 --disableexcludes=kubernetes验证下载操作正常，并且 kubeadm 版本正确：
┌──[root@vms81.liruilongs.github.io]-[~]└─$kubeadm versionkubeadm version: &version.Info{Major:"1", Minor:"22", GitVersion:"v1.22.2", GitCommit:"8b5a19147530eaac9476b0ab82980b4088bbc1b2", GitTreeState:"clean", BuildDate:"2021-09-15T21:37:34Z", GoVersion:"go1.16.8", Compiler:"gc", Platform:"linux/amd64"}验证升级计划：
┌──[root@vms81.liruilongs.github.io]-[~]└─$kubeadm upgrade plan[upgrade/config] Making sure the configuration is correct:[upgrade/config] Reading configuration from the cluster...[upgrade/config] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml'[preflight] Running pre-flight checks.[upgrade] Running cluster health checks[upgrade] Fetching available versions to upgrade to[upgrade/versions] Cluster version: v1.21.1[upgrade/versions] kubeadm version: v1.22.2[upgrade/versions] Target version: v1.22.2[upgrade/versions] Latest version in the v1.21 series: v1.21.5................选择要升级到的目标版本，运行合适的命令
┌──[root@vms81.liruilongs.github.io]-[~]└─$sudo kubeadm upgrade apply v1.22.2............upgrade/successful] SUCCESS! Your cluster was upgraded to "v1.22.2". Enjoy![upgrade/kubelet] Now that your control plane is upgraded, please proceed with upgrading your kubelets if you haven't already done so.┌──[root@vms81.liruilongs.github.io]-[~]└─$设置进入维护模式
通过将节点标记为不可调度并腾空节点为节点作升级准备：
# 将 替换为你要腾空的控制面节点名称#kubectl drain --ignore-daemonsets┌──[root@vms81.liruilongs.github.io]-[~]└─$kubectl drain vms81.liruilongs.github.io --ignore-daemonsets┌──[root@vms81.liruilongs.github.io]-[~]└─$升级 kubelet 和 kubectl
# 用最新的补丁版本号替换 1.22.x-00 中的 x#yum install -y kubelet-1.22.x-0 kubectl-1.22.x-0 --disableexcludes=kubernetes┌──[root@vms81.liruilongs.github.io]-[~]└─$yum install -y kubelet-1.22.2-0 kubectl-1.22.2-0 --disableexcludes=kubernetes 重启 kubelet
┌──[root@vms81.liruilongs.github.io]-[~]└─$sudo systemctl daemon-reload┌──[root@vms81.liruilongs.github.io]-[~]└─$sudo systemctl restart kubelet解除节点的保护
┌──[root@vms81.liruilongs.github.io]-[~]└─$kubectl uncordon vms81.liruilongs.github.ionode/vms81.liruilongs.github.io uncordonedmaster 节点版本以已经替换
┌──[root@vms81.liruilongs.github.io]-[~]└─$kubectl get nodesNAME STATUS ROLES AGE VERSIONvms81.liruilongs.github.io Ready control-plane,master 11d v1.22.2vms82.liruilongs.github.io NotReady <none> 11d v1.21.1vms83.liruilongs.github.io Ready <none> 11d v1.21.1┌──[root@vms81.liruilongs.github.io]-[~]└─$升级工作节点Node
工作节点上的升级过程应该一次执行一个节点，或者一次执行几个节点， 以不影响运行工作负载所需的最小容量。
升级 kubeadm
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible node -a "yum install -y kubeadm-1.22.2-0 --disableexcludes=kubernetes"┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible node -a "sudo kubeadm upgrade node" # 执行 "kubeadm upgrade" 对于工作节点，下面的命令会升级本地的 kubelet 配置：┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl get nodesNAME STATUSROLES AGE VERSIONvms81.liruilongs.github.io Ready control-plane,master 12d v1.22.2vms82.liruilongs.github.io Ready <none> 12d v1.21.1vms83.liruilongs.github.io Ready,SchedulingDisabled <none> 12d v1.22.2腾空节点,设置维护状态
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl drain vms82.liruilongs.github.io --ignore-daemonsetsnode/vms82.liruilongs.github.io cordonedWARNING: ignoring DaemonSet-managed Pods: kube-system/calico-node-ntm7v, kube-system/kube-proxy-nzm24node/vms82.liruilongs.github.io drained升级 kubelet 和 kubectl
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.82 -a "yum install -y kubelet-1.22.2-0 kubectl-1.22.2-0 --disableexcludes=kubernetes"重启 kubelet
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.82 -a "systemctl daemon-reload"192.168.26.82 | CHANGED | rc=0 >>┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.82 -a "systemctl restart kubelet"192.168.26.82 | CHANGED | rc=0 >>┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl get nodesNAME STATUSROLES AGE VERSIONvms81.liruilongs.github.io Ready control-plane,master 13d v1.22.2vms82.liruilongs.github.io Ready,SchedulingDisabled <none> 13d v1.22.2vms83.liruilongs.github.io Ready,SchedulingDisabled <none> 13d v1.22.2取消对节点的保护
┌──[root@vms81.liruilongs.github.io]-[~]└─$kubectl uncordon vms82.liruilongs.github.ionode/vms82.liruilongs.github.io uncordoned┌──[root@vms81.liruilongs.github.io]-[~]└─$kubectl uncordon vms83.liruilongs.github.ionode/vms83.liruilongs.github.io uncordoned┌──[root@vms81.liruilongs.github.io]-[~]└─$kubectl get nodesNAME STATUS ROLES AGE VERSIONvms81.liruilongs.github.io Ready control-plane,master 13d v1.22.2vms82.liruilongs.github.io Ready 13d v1.22.2vms83.liruilongs.github.io Ready 13d v1.22.2┌──[root@vms81.liruilongs.github.io]-[~]└─$kubeadm upgrade apply 做了以下工作：
- 检查你的集群是否处于可升级状态:
- API 服务器是可访问的
- 所有节点处于 Ready 状态
- 控制面是健康的
- 强制执行版本偏差策略。
- 确保控制面的镜像是可用的或可拉取到服务器上。
- 如果组件配置要求版本升级，则生成替代配置与/或使用用户提供的覆盖版本配置。
- 升级控制面组件或回滚（如果其中任何一个组件无法启动）。
- 应用新的 CoreDNS 和 kube-proxy 清单，并强制创建所有必需的 RBAC 规则。
- 如果旧文件在 180 天后过期，将创建 API 服务器的新证书和密钥文件并备份旧文件。
kubeadm upgrade node 在其他控制平节点上执行以下操作：
- 从集群中获取 kubeadm ClusterConfiguration。
- （可选操作）备份 kube-apiserver 证书。
- 升级控制平面组件的静态 Pod 清单。
- 为本节点升级 kubelet 配置
kubeadm upgrade node 在工作节点上完成以下工作：
- 从集群取回 kubeadm ClusterConfiguration。
- 为本节点升级 kubelet 配置。
五、Pod
环境测试
┌──[root@vms81.liruilongs.github.io]-[~]└─$kubectl get nodesNAME STATUS ROLES AGE VERSIONvms81.liruilongs.github.io Ready control-plane,master 7d23h v1.21.1vms82.liruilongs.github.io Ready <none> 7d23h v1.21.1vms83.liruilongs.github.io NotReady <none> 7d23h v1.21.1┌──[root@vms81.liruilongs.github.io]-[~]└─$cd ansible/┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible node -m ping192.168.26.82 | SUCCESS => { "ansible_facts": { "discovered_interpreter_python": "/usr/bin/python" }, "changed": false, "ping": "pong"}192.168.26.83 | SUCCESS => { "ansible_facts": { "discovered_interpreter_python": "/usr/bin/python" }, "changed": false, "ping": "pong"}┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible node -m shell -a "systemctl is-active docker"192.168.26.83 | FAILED | rc=3 >>unknownnon-zero return code192.168.26.82 | CHANGED | rc=0 >>active┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.83 -m shell -a "systemctl enable docker --now"192.168.26.83 | CHANGED | rc=0 >>Created symlink from /etc/systemd/system/multi-user.target.wants/docker.service to /usr/lib/systemd/system/docker.service.┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl get nodesNAME STATUS ROLES AGE VERSIONvms81.liruilongs.github.io Ready control-plane,master 7d23h v1.21.1vms82.liruilongs.github.io Ready <none> 7d23h v1.21.1vms83.liruilongs.github.io Ready <none> 7d23h v1.21.1┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$帮助文档的使用
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl explain --help┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl explain podsKIND: PodVERSION: v1DESCRIPTION: Pod is a collection of containers that can run on a host. This resource is created by clients and scheduled onto hosts.FIELDS: apiVersion <string> .... kind <string> ..... metadata <Object> ..... spec <Object> ..... status<Object> ....┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl explain pods.metadataKIND: PodVERSION: v1创建Pod的方式
新建命名空间:
kubectl config set-context context1 --namespace=liruilong-pod-create
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$mkdir k8s-pod-create┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$cd k8s-pod-create/┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl create ns liruilong-pod-createnamespace/liruilong-pod-create created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl config viewapiVersion: v1clusters:- cluster: certificate-authority-data: DATA+OMITTED server: https://192.168.26.81:6443 name: cluster1contexts:- context: cluster: cluster1 namespace: kube-system user: kubernetes-admin1 name: context1current-context: context1kind: Configpreferences: {}users:- name: kubernetes-admin1 user: client-certificate-data: REDACTED client-key-data: REDACTED┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get nsNAME STATUS AGEdefault Active 8dkube-node-lease Active 8dkube-public Active 8dkube-system Active 8dliruilongActive 7d10hliruilong-pod-create Active 4m18s┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl config set-context context1 --namespace=liruilong-pod-createContext "context1" modified.┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$docker pull nginxUsing default tag: latestlatest: Pulling from library/nginxb380bbd43752: Pull completefca7e12d1754: Pull complete745ab57616cb: Pull completea4723e260b6f: Pull complete1c84ebdff681: Pull complete858292fd2e56: Pull completeDigest: sha256:644a70516a26004c97d0d85c7fe1d0c3a67ea8ab7ddf4aff193d9f301670cf36Status: Downloaded newer image for nginx:latestdocker.io/library/nginx:latest命令行的方式创建pod
kubectl run podcommon --image=nginx --image-pull-policy=IfNotPresent --labels="name=liruilong" --env="name=liruilong"
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl run podcommon --image=nginx --image-pull-policy=IfNotPresent --labels="name=liruilong" --env="name=liruilong"pod/podcommon created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get podsNAME READY STATUSRESTARTS AGEpodcommon 0/1 ContainerCreating 0 12s查看调度节点
kubectl get pods -o wide
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl run pod-demo --image=nginx --labels=name=nginx --env="user=liruilong" --port=8888 --image-pull-policy=IfNotPresentpod/pod-demo created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods | grep pod-pod-demo 1/1 Running 0 73s┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -o wideNAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESmysql-577h7 1/1 Running 0 19m 10.244.70.39 vms83.liruilongs.github.io <none> <none>myweb-4xlc5 1/1 Running 0 18m 10.244.70.40 vms83.liruilongs.github.io <none> <none>myweb-ltqdt 1/1 Running 0 18m 10.244.171.148 vms82.liruilongs.github.io <none> <none>pod-demo 1/1 Running 0 94s 10.244.171.149 vms82.liruilongs.github.io <none> <none>poddemo1/1 Running 0 8m22s 10.244.70.41 vms83.liruilongs.github.io <none> <none>┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$删除pod
kubectl delete pod pod-demo --force
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl delete pod pod-demo --forcewarning: Immediate deletion does not wait for confirmation that the running resource has been terminated. The resource may continue to run on the cluster indefinitely.pod "pod-demo" force deleted┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods | grep pod-┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$生成yaml文件的方式创建pod
kubectl run pod-demo --image=nginx --image-pull-policy=IfNotPresent --dry-run=client -o yaml >pod-demo.yaml
yaml文件的获取方法:
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create] # yaml文件的获取方法:└─$kubectl run pod-demo --image=nginx --image-pull-policy=IfNotPresent --dry-run=client -o yamlapiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: pod-demo name: pod-demospec: containers: - image: nginx imagePullPolicy: IfNotPresent name: pod-demo resources: {} dnsPolicy: ClusterFirst restartPolicy: Alwaysstatus: {}yaml文件创建pod
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl run pod-demo --image=nginx --image-pull-policy=IfNotPresent --dry-run=client -o yaml >pod-demo.yaml┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$cat pod-demo.yamlapiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: pod-demo name: pod-demospec: containers: - image: nginx imagePullPolicy: IfNotPresent name: pod-demo resources: {} dnsPolicy: ClusterFirst restartPolicy: Alwaysstatus: {}┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl apply -f pod-demo.yamlpod/pod-demo created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get podsNAME READY STATUS RESTARTS AGEpod-demo 1/1 Running 0 12spodcommon 1/1 Running 0 13m┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -o wideNAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESpod-demo 1/1 Running 0 27s 10.244.70.4 vms83.liruilongs.github.io <none> <none>podcommon 1/1 Running 0 13m 10.244.70.3 vms83.liruilongs.github.io <none> <none>┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl delete pod pod-demopod "pod-demo" deleted┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -o wideNAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESpodcommon 1/1 Running 0 14m 10.244.70.3 vms83.liruilongs.github.io <none> <none>┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$创建pod时指定运行命令。替换镜像中CMD的命令
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$# 创建pod时指定运行命令。替换镜像中CMD的命令┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl run comm-pod --image=nginx --image-pull-policy=IfNotPresent --dry-run=client -o yaml -- "echo liruilong"apiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: comm-pod name: comm-podspec: containers: - args: - echo liruilong image: nginx imagePullPolicy: IfNotPresent name: comm-pod resources: {} dnsPolicy: ClusterFirst restartPolicy: Alwaysstatus: {}┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl run comm-pod --image=nginx --image-pull-policy=IfNotPresent --dry-run=client -o yaml -- sh -c "echo liruilong"apiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: comm-pod name: comm-podspec: containers: - args: - sh - -c - echo liruilong image: nginx imagePullPolicy: IfNotPresent name: comm-pod resources: {} dnsPolicy: ClusterFirst restartPolicy: Alwaysstatus: {}┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl delete -f comm-pod.yaml删除pod
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl run comm-pod --image=nginx --image-pull-policy=IfNotPresent --dry-run=client -o yaml -- sh c "echo liruilong" > comm-pod.yaml┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl apply -f comm-pod.yamlpod/comm-pod created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get podsNAME READY STATUS RESTARTS AGEcomm-pod 0/1 CrashLoopBackOff 3 (27s ago) 72smysql-577h7 1/1 Running 0 54mmyweb-4xlc5 1/1 Running 0 53mmyweb-ltqdt 1/1 Running 0 52mpoddemo1/1 Running 0 42m┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl delete -f comm-pod.yamlpod "comm-pod" deleted┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$批量创建pod
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$sed 's/demo/demo1/' demo.yaml | kubectl apply -f -pod/demo1 created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$sed 's/demo/demo2/' demo.yaml | kubectl create -f -pod/demo2 created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get podsNAME READY STATUS RESTARTS AGEdemo 0/1 CrashLoopBackOff 7 (4m28s ago) 18mdemo1 1/1 Running 0 49sdemo2 1/1 Running 0 26smysql-d4n6j 1/1 Running 0 23mmyweb-85kf8 1/1 Running 0 22mmyweb-z4qnz 1/1 Running 0 22m┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -o wideNAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESdemo1 1/1 Running 0 3m29s 10.244.70.32 vms83.liruilongs.github.io <none> <none>demo2 1/1 Running 0 3m6s 10.244.70.33 vms83.liruilongs.github.io <none> <none>mysql-d4n6j 1/1 Running 0 25m 10.244.171.137 vms82.liruilongs.github.io <none> <none>myweb-85kf8 1/1 Running 0 25m 10.244.171.138 vms82.liruilongs.github.io <none> <none>myweb-z4qnz 1/1 Running 0 25m 10.244.171.139 vms82.liruilongs.github.io <none> <none>┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$容器共享pod的网络空间的。即使用同一个IP地址
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.83 -m shell -a "docker ps | grep demo1"192.168.26.83 | CHANGED | rc=0 >>0d644ad550f5 87a94228f133"/docker-entrypoint.…" 8 minutes ago Up 8 minutesk8s_demo1_demo1_liruilong-pod-create_b721b109-a656-4379-9d3c-26710dadbf70_00bcffe0f8e2d registry.aliyuncs.com/google_containers/pause:3.4.1 "/pause" 8 minutes ago Up 8 minutesk8s_POD_demo1_liruilong-pod-create_b721b109-a656-4379-9d3c-26710dadbf70_0┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.83 -m shell -a "docker inspect 0d644ad550f5 | grep -i ipaddress "192.168.26.83 | CHANGED | rc=0 >> "SecondaryIPAddresses": null, "IPAddress": "",┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$# 容器共享pod的网络空间的。┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$一个pod内创建多个容器
yaml 文件编写
apiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: comm-pod name: comm-podspec: containers: - args: - sh - -c - echo liruilong;sleep 10000 image: nginx imagePullPolicy: IfNotPresent name: comm-pod0 resources: {} - name: comm-pod1 image: nginx imagePullPolicy: IfNotPresent dnsPolicy: ClusterFirst restartPolicy: Alwaysstatus: {}创建 pod
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl delete -f comm-pod.yamlpod "comm-pod" deleted┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$vim comm-pod.yaml┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl apply -f comm-pod.yamlpod/comm-pod created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get podsNAME READY STATUS RESTARTS AGEcomm-pod 2/2 Running 0 20smysql-577h7 1/1 Running 0 89mmyweb-4xlc5 1/1 Running 0 87mmyweb-ltqdt 1/1 Running 0 87m查看标签，指定标签过滤
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods --show-labelsNAME READY STATUS RESTARTS AGE LABELScomm-pod 2/2 Running 0 4m43s run=comm-podmysql-577h7 1/1 Running 0 93m app=mysqlmyweb-4xlc5 1/1 Running 0 92m app=mywebmyweb-ltqdt 1/1 Running 0 91m app=myweb┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -l run=comm-podNAMEREADY STATUS RESTARTS AGEcomm-pod 2/2 Running 0 5m12s┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$镜像的下载策略
--image-pull-policy
- Always 每次都下载最新镜像
- Never 只使用本地镜像，从不下载
- IfNotPresent 本地没有才下载
pod的重启策略–单个容器正常退出
restartPolicy
- Always 总是重启
- OnFailure 非正常退出才重启
- Never 从不重启
labels 标签
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$# 每个对象都有标签┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get nodes --show-labelsNAME STATUS ROLES AGE VERSION LABELSvms81.liruilongs.github.io Ready control-plane,master 8d v1.21.1 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=vms81.liruilongs.github.io,kubernetes.io/os=linux,node-role.kubernetes.io/control-plane=,node-role.kubernetes.io/master=,node.kubernetes.io/exclude-from-external-load-balancers=vms82.liruilongs.github.io Ready <none> 8d v1.21.1 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=vms82.liruilongs.github.io,kubernetes.io/os=linuxvms83.liruilongs.github.io Ready <none> 8d v1.21.1 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=vms83.liruilongs.github.io,kubernetes.io/os=linux┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods --show-labelsNAME READY STATUS RESTARTS AGE LABELSpodcommon 1/1 Running 0 87s name=liruilong每个Pod都有一个pause镜像
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.83 -m shell -a "docker ps | grep podcomm"192.168.26.83 | CHANGED | rc=0 >>c04e155aa25d nginx"/docker-entrypoint.…" 21 minutes ago Up 21 minutes k8s_podcommon_podcommon_liruilong-pod-create_dbfc4fcd-d62b-4339-9f15-0a48802f60ad_0309925812d42 registry.aliyuncs.com/google_containers/pause:3.4.1 "/pause" 21 minutes ago Up 21 minutes k8s_POD_podcommon_liruilong-pod-create_dbfc4fcd-d62b-4339-9f15-0a48802f60ad_0pod的状态
| pod的状态 | – |
|---|---|
Pending pod |
因为其他的原因导致pod准备开始创建 还没有创建（卡住了） |
Running pod |
已经被调度到节点上，且容器工作正常 |
Completed pod |
里所有容器正常退出 |
error/CrashLoopBackOff |
创建的时候就出错，属于内部原因 |
imagePullBackoff |
创建pod的时候，镜像下载失败 |
Pod的基本操作
在pod里执行命令，查看pod详细信息。查看pod日志
kubectl exec 命令kubectl exec -it pod sh #如果pod里有多个容器，则命令是在第一个容器里执行kubectl exec -it demo -c demo1 sh # 指定容器kubectl describe pod pod名kubectl logs pod名 -c 容器名 #如果有多个容器的话 查看日志。kubectl edit pod pod名 # 部分可以修改，有些不能修改查看pod详细信息
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl describe pod demo1Name: demo1Namespace: liruilong-pod-createPriority: 0Node: vms83.liruilongs.github.io/192.168.26.83Start Time: Wed, 20 Oct 2021 22:27:15 +0800Labels:run=demo1Annotations: cni.projectcalico.org/podIP: 10.244.70.32/32cni.projectcalico.org/podIPs: 10.244.70.32/32Status:RunningIP: 10.244.70.32IPs: IP: 10.244.70.32Containers: demo1: Container ID: docker://0d644ad550f59029036fd73d420d4d2c651801dd12814bb26ad8e979dc0b59c1 Image: nginx Image ID:docker-pullable://nginx@sha256:644a70516a26004c97d0d85c7fe1d0c3a67ea8ab7ddf4aff193d9f301670cf36 Port: <none> Host Port: <none> State: Running Started: Wed, 20 Oct 2021 22:27:20 +0800 Ready: True Restart Count: 0 Environment: <none> Mounts: /var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-scc89 (ro)Conditions: TypeStatus InitializedTrue Ready True ContainersReady True PodScheduled TrueVolumes: kube-api-access-scc89: Type: Projected (a volume that contains injected data from multiple sources) TokenExpirationSeconds: 3607 ConfigMapName: kube-root-ca.crt ConfigMapOptional:<nil> DownwardAPI: trueQoS Class: BestEffortNode-Selectors:<none>Tolerations: node.kubernetes.io/not-ready:NoExecute op=Exists for 300s node.kubernetes.io/unreachable:NoExecute op=Exists for 300sEvents: Type Reason Age From Message ---- ------ ---- ---- ------- Normal Scheduled 13m default-scheduler Successfully assigned liruilong-pod-create/demo1 to vms83.liruilongs.github.io Normal Pulled 13m kubelet Container image "nginx" already present on machine Normal Created 13m kubelet Created container demo1 Normal Started 13m kubelet Started container demo1在pod里执行命令
多个容器需要用-c指定
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl exec -it demo1 -- ls /tmp┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl exec -it demo1 -- sh# lsbin dev docker-entrypoint.sh home lib64 mnt proc run srv tmp varboot docker-entrypoint.d etc lib media opt root sbin sys usr# exit┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl exec -it demo1 -- bashroot@demo1:/# lsbin dev docker-entrypoint.sh home lib64 mnt proc run srv tmp varboot docker-entrypoint.d etc lib media opt root sbin sys usrroot@demo1:/# exitexit┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl exec comm-pod -c comm-pod1 -- echo liruilongliruilong┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl exec -it comm-pod -c comm-pod1 -- sh# lsbin boot dev docker-entrypoint.d docker-entrypoint.sh etc home lib lib64 media mnt opt proc root run sbin srv sys tmp usr var# exit┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$#查看日志
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl logs demo1/docker-entrypoint.sh: /docker-entrypoint.d/ is not empty, will attempt to perform configuration/docker-entrypoint.sh: Looking for shell scripts in /docker-entrypoint.d//docker-entrypoint.sh: Launching /docker-entrypoint.d/10-listen-on-ipv6-by-default.sh10-listen-on-ipv6-by-default.sh: info: Getting the checksum of /etc/nginx/conf.d/default.conf10-listen-on-ipv6-by-default.sh: info: Enabled listen on IPv6 in /etc/nginx/conf.d/default.conf/docker-entrypoint.sh: Launching /docker-entrypoint.d/20-envsubst-on-templates.sh/docker-entrypoint.sh: Launching /docker-entrypoint.d/30-tune-worker-processes.sh/docker-entrypoint.sh: Configuration complete; ready for start up2021/10/20 14:27:21 [notice] 1#1: using the "epoll" event method2021/10/20 14:27:21 [notice] 1#1: nginx/1.21.32021/10/20 14:27:21 [notice] 1#1: built by gcc 8.3.0 (Debian 8.3.0-6)2021/10/20 14:27:21 [notice] 1#1: OS: Linux 3.10.0-693.el7.x86_642021/10/20 14:27:21 [notice] 1#1: getrlimit(RLIMIT_NOFILE): 1048576:10485762021/10/20 14:27:21 [notice] 1#1: start worker processes2021/10/20 14:27:21 [notice] 1#1: start worker process 322021/10/20 14:27:21 [notice] 1#1: start worker process 33┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$拷贝文件
和docke一样的，可以相互拷贝
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl cp /etc/hosts comm-pod:/usr/share/nginx/html -c comm-pod1┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl exec comm-pod -c comm-pod1 -- ls /usr/share/nginx/html50x.htmlhostsindex.html┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$pod里运行命令command的执行方式
apiVersion: v1kind: Podmetadata: name: myapp-pod labels: app: myappspec: containers: - name: myapp-container image: busybox command: ['sh', '-c', 'echo OK! && sleep 60']apiVersion: v1kind: Podmetadata: name: myapp-pod labels: app: myappspec: containers: - name: myapp-container image: busybox command: - sh - -c - echo OK! && sleep 60pod生命周期，优雅的关闭pod
pod的延期删除
k8s对于pod的删除有一个延期的删除期，即宽限期，这个时间默认为30s,如果删除时加了 --force选项，就会强制删除。
在删除宽限期内，节点状态被标记为treminating ,宽限期结束后删掉pod，这里的宽限期通过参数 terminationGracePeriodSeconds 设定
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl explain pod.spec.... terminationGracePeriodSeconds <integer> pod需要优雅终止的可选持续时间(以秒为单位)。可在删除请求中增加。值必须是非负整数。 值0表示通过kill信号立即停止(没有机会关机)。如果该值为null，则使用默认的宽限期。 宽限期是在pod中运行的进程收到终止信号后的持续时间(以秒为单位)，以及进程被kill信号强制停止的时间。 设置此值比流程的预期清理时间长。默认为30秒。如果pod里面是Nginx进程，就不行，Nginx的处理信号的方式和k8s不同，当我们使用Nginx作为镜像来生成一个个pod的时候，pod里面的Nginx进程就会被很快的关闭，之后的pod也会被删除，并不会使用k8s的宽限期
当某个pod正在被使用是，突然关闭，那这个时候我们还想处理一些事情，这里可以用 pod hook
pod hook(钩子)
hook是一个很常见的功能，有时候也称回调，即在到达某一预期事件时触发的操作，比如 前端框架 Vue 的生命周期回调函数，java 虚拟机 JVM 在进程结束时的钩子线程。
在pod的整个生命周期内，有两个回调可以使用
| 两个回调可以使用 |
|---|
| postStart： 当创建pod的时候调用，会随着pod里的主进程同时运行，并行操作，没有先后顺序 |
| preStop： 当删除pod的时候创建，要先运行perStop里的程序，之后在关闭pod,这里的preStop必须是在pod的宽限期内完成，没有完成pod也会被强制删除 |
下面我们创建一个带钩子的pod
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$cat demo.yamlapiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: demo name: demospec: containers: - image: nginx imagePullPolicy: IfNotPresent name: demo resources: {} dnsPolicy: ClusterFirst restartPolicy: Alwaysstatus: {}通过帮助文档查看宽限期的命令
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl explain pod.spec | grep termin* terminationGracePeriodSeconds <integer> Optional duration in seconds the pod needs to terminate gracefully. May be the pod are sent a termination signal and the time when the processes are┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$修改yaml文件
demo.yaml
apiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: demo name: demospec: terminationGracePeriodSeconds: 600 containers: - image: nginx imagePullPolicy: IfNotPresent name: demo resources: {} lifecycle: postStart: exec: command: ["bin/sh", "-c","echo liruilong`date` >> /liruilong"] preStop: exec: command: ["bin/sh","-c","use/sbin/nginx -s quit"] dnsPolicy: ClusterFirst restartPolicy: Alwaysstatus: {}┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$vim demo.yaml┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl apply -f demo.yamlpod/demo created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get podsNAME READY STATUS RESTARTS AGEdemo 1/1 Running 0 21smysql-cp7qd 1/1 Running 0 2d13hmyweb-bh9g7 1/1 Running 0 2d4hmyweb-zdc4q 1/1 Running 0 2d13h┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl exec -it demo -- bin/bashroot@demo:/# lsbin dev docker-entrypoint.sh home lib64 media opt root sbin sys usrboot docker-entrypoint.d etc lib liruilong mnt proc run srv tmp varroot@demo:/# cat liruilongliruilongSun Nov 14 05:10:51 UTC 2021root@demo:/#这里关闭的话，主进程不会等到宽限期结束，会找Ngixn收到关闭信号时直接关闭
初始化Pod
所谓初始化pod，类比java中的构造概念，如果pod的创建命令类比java的构造函数的话，那么初始化容器即为构造块，java中构造块是在构造函数之前执行的一些语句块。初始化容器即为主容器构造前执行的一些语句
| 初始化规则: |
|---|
| 它们总是运行到完成。 |
| 每个都必须在下一个启动之前成功完成。 |
| 如果 Pod 的 Init 容器失败，Kubernetes 会不断地重启该 Pod，直到 Init 容器成功为止。然而，如果 Pod 对应的restartPolicy 为 Never，它不会重新启动。 |
| Init 容器支持应用容器的全部字段和特性，但不支持 Readiness Probe，因为它们必须在 Pod 就绪之前运行完成。 |
| 如果为一个 Pod 指定了多个 Init 容器，那些容器会按顺序一次运行一个。 每个 Init 容器必须运行成功，下一个才能够运行。 |
因为Init容器可能会被重启、重试或者重新执行，所以 Init 容器的代码应该是幂等的。特别地，被写到EmptyDirs 中文件的代码，应该对输出文件可能已经存在做好准备。 |
在 Pod 上使用 activeDeadlineSeconds，在容器上使用 livenessProbe，这样能够避免Init容器一直失败。 这就为 Init 容器活跃设置了一个期限。 |
在Pod中的每个app 和Init容器的名称必须唯一；与任何其它容器共享同一个名称，会在验证时抛出错误。 |
对 Init容器spec 的修改，被限制在容器 image字段中。 更改 Init 容器的image字段，等价于重启该Pod。 |
初始化容器在pod资源文件里 的initContainers里定义，和containers是同一级
通过初始化容器修改内核参数
创建初始化容器，这里我们通过初始化容器修改swap的一个内核参数为0，即使用交换分区频率为0
Alpine 操作系统是一个面向安全的轻型 Linux 发行版。它不同于通常 Linux 发行版，Alpine 采用了 musl libc 和 busybox 以减小系统的体积和运行时资源消耗，但功能上比 busybox 又完善的多，因此得到开源社区越来越多的青睐。在保持瘦身的同时，Alpine 还提供了自己的包管理工具 apk，可以通过 https://pkgs.alpinelinux.org/packages 网站上查询包信息，也可以直接通过 apk 命令直接查询和安装各种软件
YAML文件编写
apiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: pod-init name: pod-initspec: containers: - image: nginx imagePullPolicy: IfNotPresent name: pod1-init resources: {} dnsPolicy: ClusterFirst restartPolicy: Always initContainers: - image: alpine name: init imagePullPolicy: IfNotPresent command: ["/bin/sh","-c","sbin/sysctl -w vm.swappiness=0"] securityContext: privileged: truestatus: {}查看系统默认值，运行pod
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$cat /proc/sys/vm/swappiness30┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$vim pod_init.yaml┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl apply -f pod_init.yamlpod/pod-init created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get podsNAME READY STATUS RESTARTS AGEmysql-hhjnk 1/1 Running 0 3d9hmyweb-bn5h4 1/1 Running 0 3d9hmyweb-h8jkc 1/1 Running 0 3d9hpod-init 0/1 PodInitializing 0 7s┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get podsNAME READY STATUS RESTARTS AGEmysql-hhjnk 1/1 Running 0 3d9hmyweb-bn5h4 1/1 Running 0 3d9hmyweb-h8jkc 1/1 Running 0 3d9hpod-init 1/1 Running 0 14spod创建成功验证一下
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pod -o wideNAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESmysql-hhjnk 1/1 Running 0 3d9h 10.244.171.162 vms82.liruilongs.github.io <none> <none>myweb-bn5h4 1/1 Running 0 3d9h 10.244.171.163 vms82.liruilongs.github.io <none> <none>myweb-h8jkc 1/1 Running 0 3d9h 10.244.171.160 vms82.liruilongs.github.io <none> <none>pod-init 1/1 Running 0 11m 10.244.70.54 vms83.liruilongs.github.io <none> <none>┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$cd ..┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.83 -m ping192.168.26.83 | SUCCESS => { "ansible_facts": { "discovered_interpreter_python": "/usr/bin/python" }, "changed": false, "ping": "pong"}┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible 192.168.26.83 -m shell -a "cat /proc/sys/vm/swappiness"192.168.26.83 | CHANGED | rc=0 >>0┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$初始化容器和普通容器数据共享
配置文件编写
这里我们配置一个共享卷，然后再初始化容器里同步数据到普通的容器里。
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$cp pod_init.yaml pod_init1.yaml┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$vim pod_init1.yaml 31L, 604C 已写入┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl apply -f pod_init1.yamlpod/pod-init1 created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get podsNAME READY STATUS RESTARTS AGEmysql-hhjnk 1/1 Running 0 3d9hmyweb-bn5h4 1/1 Running 0 3d9hmyweb-h8jkc 1/1 Running 0 3d9hpod-init 1/1 Running 0 31mpod-init1 1/1 Running 0 10s┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods pod-init1NAME READY STATUS RESTARTS AGEpod-init1 1/1 Running 0 30s┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl exec -it pod-init1 /bin/shkubectl exec [POD] [COMMAND] is DEPRECATED and will be removed in a future version. Use kubectl exec [POD] -- [COMMAND] instead.Defaulted container "pod1-init" out of: pod1-init, init (init)# ls2021 boot docker-entrypoint.d etc lib media opt root sbin sys usrbin dev docker-entrypoint.sh home lib64 mnt proc run srv tmp var# cd 2021;lsliruilong.txt#静态pod
正常情况下，pod是在master上统一管理的,所谓静态pod就是，即不是由master上创建调度的，是属于node自身特的pod，在node上只要启动kubelet之后，就会自动的创建的pod。这里理解的话，结合java静态熟悉，静态方法理解，即的node节点初始化的时候需要创建的一些pod
比如 kubeadm的安装k8s的话，所以的服务都是通过容器的方式运行的。相比较二进制的方式方便很多,这里的话，那么涉及到master节点的相关组件在没有k8s环境时是如何运行，构建master节点的，这里就涉及到静态pod的问题。
工作节点创建 静态pod
工作节点查看kubelet 启动参数配置文件
| /usr/lib/systemd/system/kubelet.service.d/10-kubeadm.conf |
|---|
--pod-manifest-path=/etc/kubernetes/kubelet.d |
 |
Environment="KUBELET_KUBECONFIG_ARGS=--bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf --kubeconfig=/etc/kubernetes/kubelet.conf --pod-manifest-path=/etc/kubernetes/kubelet.d" |
mkdir -p /etc/kubernetes/kubelet.d |
首先需要在配置文件中添加加载静态pod 的yaml文件位置
先在本地改配置文件，使用ansible发送到node节点上，
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$vim /usr/lib/systemd/system/kubelet.service.d/10-kubeadm.conf┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$cat /usr/lib/systemd/system/kubelet.service.d/10-kubeadm.conf# Note: This dropin only works with kubeadm and kubelet v1.11+[Service]Environment="KUBELET_KUBECONFIG_ARGS=--bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf --kubeconfig=/etc/kubernetes/kubelet.conf --pod-manifest-path=/etc/kubernetes/kubelet.d"Environment="KUBELET_CONFIG_ARGS=--config=/var/lib/kubelet/config.yaml"# This is a file that "kubeadm init" and "kubeadm join" generates at runtime, populating the KUBELET_KUBEADM_ARGS variable dynamicallyEnvironmentFile=-/var/lib/kubelet/kubeadm-flags.env# This is a file that the user can use for overrides of the kubelet args as a last resort. Preferably, the user should use# the .NodeRegistration.KubeletExtraArgs object in the configuration files instead. KUBELET_EXTRA_ARGS should be sourced from this file.EnvironmentFile=-/etc/sysconfig/kubeletExecStart=ExecStart=/usr/bin/kubelet $KUBELET_KUBECONFIG_ARGS $KUBELET_CONFIG_ARGS $KUBELET_KUBEADM_ARGS $KUBELET_EXTRA_ARGS┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$mkdir -p /etc/kubernetes/kubelet.d修改配置后需要加载配置文件重启kubelet
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible node -m copy -a "src=/usr/lib/systemd/system/kubelet.service.d/10-kubeadm.conf dest=/usr/lib/systemd/system/kubelet.service.d/10-kubeadm.conf force=yes"192.168.26.82 | CHANGED => { "ansible_facts": { "discovered_interpreter_python": "/usr/bin/python" }, "changed": true, "checksum": "13994d828e831f4aa8760c2de36e100e7e255526", "dest": "/usr/lib/systemd/system/kubelet.service.d/10-kubeadm.conf", "gid": 0, "group": "root", "md5sum": "0cfe0f899ea24596f95aa2e175f0dd08", "mode": "0644", "owner": "root", "size": 946, "src": "/root/.ansible/tmp/ansible-tmp-1637403640.92-32296-63660481173900/source", "state": "file", "uid": 0}192.168.26.83 | CHANGED => { "ansible_facts": { "discovered_interpreter_python": "/usr/bin/python" }, "changed": true, "checksum": "13994d828e831f4aa8760c2de36e100e7e255526", "dest": "/usr/lib/systemd/system/kubelet.service.d/10-kubeadm.conf", "gid": 0, "group": "root", "md5sum": "0cfe0f899ea24596f95aa2e175f0dd08", "mode": "0644", "owner": "root", "size": 946, "src": "/root/.ansible/tmp/ansible-tmp-1637403640.89-32297-164984088437265/source", "state": "file", "uid": 0}┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible node -m shell -a "mkdir -p /etc/kubernetes/kubelet.d"192.168.26.83 | CHANGED | rc=0 >>192.168.26.82 | CHANGED | rc=0 >>┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible node -m shell -a "systemctl daemon-reload"192.168.26.82 | CHANGED | rc=0 >>192.168.26.83 | CHANGED | rc=0 >>┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible node -m shell -a "systemctl restart kubelet"192.168.26.83 | CHANGED | rc=0 >>192.168.26.82 | CHANGED | rc=0 >>┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$现在我们需要到Node的/etc/kubernetes/kubelet.d里创建一个yaml文件，然后根据这个yaml文件，创建一个pod，这样创建出来的node，是不会接受master的管理的。我们同样使用ansible的方式来处理
default名称空间里创建两个静态pod
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$cat static-pod.yamlapiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: pod-static name: pod-static namespeace: defaultspec: containers: - image: nginx imagePullPolicy: IfNotPresent name: pod-demo resources: {} dnsPolicy: ClusterFirst restartPolicy: Alwaysstatus: {}┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible node -m copy -a "src=./static-pod.yaml dest=/etc/kubernetes/kubelet.d/static-pod.yaml"192.168.26.83 | CHANGED => { "ansible_facts": { "discovered_interpreter_python": "/usr/bin/python" }, "changed": true, "checksum": "9b059b0acb4cd99272809d1785926092816f8771", "dest": "/etc/kubernetes/kubelet.d/static-pod.yaml", "gid": 0, "group": "root", "md5sum": "41515d4c5c116404cff9289690cdcc20", "mode": "0644", "owner": "root", "size": 302, "src": "/root/.ansible/tmp/ansible-tmp-1637474358.05-72240-139405051351544/source", "state": "file", "uid": 0}192.168.26.82 | CHANGED => { "ansible_facts": { "discovered_interpreter_python": "/usr/bin/python" }, "changed": true, "checksum": "9b059b0acb4cd99272809d1785926092816f8771", "dest": "/etc/kubernetes/kubelet.d/static-pod.yaml", "gid": 0, "group": "root", "md5sum": "41515d4c5c116404cff9289690cdcc20", "mode": "0644", "owner": "root", "size": 302, "src": "/root/.ansible/tmp/ansible-tmp-1637474357.94-72238-185516913523170/source", "state": "file", "uid": 0}node检查一下，配置文件
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible node -m shell -a " cat /etc/kubernetes/kubelet.d/static-pod.yaml"192.168.26.83 | CHANGED | rc=0 >>apiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: pod-static name: pod-static namespeace: defaultspec: containers: - image: nginx imagePullPolicy: IfNotPresent name: pod-demo resources: {} dnsPolicy: ClusterFirst restartPolicy: Alwaysstatus: {}192.168.26.82 | CHANGED | rc=0 >>apiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: pod-static name: pod-static namespeace: defaultspec: containers: - image: nginx imagePullPolicy: IfNotPresent name: pod-demo resources: {} dnsPolicy: ClusterFirst restartPolicy: Alwaysstatus: {}┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$查看静态pod
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl get pod -n defaultNAME READY STATUS RESTARTS AGEpod-static-vms82.liruilongs.github.io 1/1 Running 0 8m17spod-static-vms83.liruilongs.github.io 1/1 Running 0 9m3s┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible node -m shell -a "rm -rf /etc/kubernetes/kubelet.d/static-pod.yaml"master 节点创建pod
这里我们换一种方式创建一个pod，通过 KUBELET_CONFIG_ARGS=--config=/var/lib/kubelet/config.yaml中定义的静态pod位置的方式创建pod
这里需要注意的是如果master节点是使用 --pod-manifest-path=/etc/kubernetes/kubelet.d的方式的话，k8s就会无法启动，因为--pod-manifest-path会覆盖staticPodPath: /etc/kubernetes/manifests。
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$cat /usr/lib/systemd/system/kubelet.service.d/10-kubeadm.conf# Note: This dropin only works with kubeadm and kubelet v1.11+[Service]Environment="KUBELET_KUBECONFIG_ARGS=--bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf --kubeconfig=/etc/kubernetes/kubelet.conf "Environment="KUBELET_CONFIG_ARGS=--config=/var/lib/kubelet/config.yaml"# This is a file that "kubeadm init" and "kubeadm join" generates at runtime, populating the KUBELET_KUBEADM_ARGS variable dynamicallyEnvironmentFile=-/var/lib/kubelet/kubeadm-flags.env# This is a file that the user can use for overrides of the kubelet args as a last resort. Preferably, the user should use# the .NodeRegistration.KubeletExtraArgs object in the configuration files instead. KUBELET_EXTRA_ARGS should be sourced from this file.EnvironmentFile=-/etc/sysconfig/kubeletExecStart=ExecStart=/usr/bin/kubelet $KUBELET_KUBECONFIG_ARGS $KUBELET_CONFIG_ARGS $KUBELET_KUBEADM_ARGS $KUBELET_EXTRA_ARGS┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$grep static /var/lib/kubelet/config.yamlstaticPodPath: /etc/kubernetes/manifests┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$/etc/kubernetes/manifests/ 里面放着k8s环境需要的一些静态pod组件
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ls -l /etc/kubernetes/manifests/总用量 16-rw------- 1 root root 2284 10月 19 00:09 etcd.yaml-rw------- 1 root root 3372 10月 19 00:10 kube-apiserver.yaml-rw------- 1 root root 2893 10月 19 00:10 kube-controller-manager.yaml-rw------- 1 root root 1479 10月 19 00:10 kube-scheduler.yaml┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$直接copy之前的配置文件在master节点创建静态pod，并检查
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$cp static-pod.yaml /etc/kubernetes/manifests/static-pod.yaml┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl get pods -n defaultNAME READY STATUS RESTARTS AGEpod-static-vms81.liruilongs.github.io 1/1 Running 0 13spod-static-vms82.liruilongs.github.io 1/1 Running 0 34mpod-static-vms83.liruilongs.github.io 1/1 Running 0 35m┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$rm -rf /etc/kubernetes/manifests/static-pod.yaml调度的三个对象
待调度Pod列表
有多少个pod需要调度，即创建的pod列表
可用node列表
有那些节点可以参与调度，排除有污点，端口的一些node
调度算法
主机过滤
NoDiskConflictPodFitsResourcesPodFitsPortsMatchNodeSelectorHostNameNoVolumeZoneConflictPodToleratesNodeTaintsCheckNodeMemoryPressureCheckNodeDiskPressureMaxEBSVolumeCountMaxGCEPDVolumeCountMaxAzureDiskVolumeCountMatchInterPodAffinityGeneralPredicatesNodeVolumeNodeConflic
主机打分
| 分数项 | 公式 |
|---|---|
| LeastRequestedPriority | score=cpu ( ( capacity - sum ( requested ) ) * 10 / capacity) + memory ( ( capacity - sum ( requested) ) * 10 / capacity )/2 |
| BalanceResourceAllocation | score = 10 -abs ( cpuFraction - memoryFraction ) * 10 |
| CalculateSpreadPriority | Score = 10 * ((maxCount -counts)/ (maxCount)) |
手动指定pod的运行位置:pod调度
| 标签设置 |
|---|
| 查看 |
| 设置 |
| 取消 |
| 所有节点设置 |
可以给node设置指定的标签，然后我们可以在创建pod里指定node标签
查看节点pod：kubectl get node --show-labels
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl get node --show-labelsNAME STATUS ROLES AGE VERSION LABELSvms81.liruilongs.github.io Ready control-plane,master 45d v1.22.2 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=vms81.liruilongs.github.io,kubernetes.io/os=linux,node-role.kubernetes.io/control-plane=,node-role.kubernetes.io/master=,node.kubernetes.io/exclude-from-external-load-balancers=vms82.liruilongs.github.io Ready <none> 45d v1.22.2 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=vms82.liruilongs.github.io,kubernetes.io/os=linuxvms83.liruilongs.github.io Ready <none> 45d v1.22.2 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=vms83.liruilongs.github.io,kubernetes.io/os=linux给节点设置标签
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl label node vms82.liruilongs.github.io disktype=node1node/vms82.liruilongs.github.io labeled┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl label node vms83.liruilongs.github.io disktype=node2node/vms83.liruilongs.github.io labeled┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl get node --show-labelsNAME STATUS ROLES AGE VERSION LABELSvms81.liruilongs.github.io Ready control-plane,master 45d v1.22.2 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=vms81.liruilongs.github.io,kubernetes.io/os=linux,node-role.kubernetes.io/control-plane=,node-role.kubernetes.io/master=,node.kubernetes.io/exclude-from-external-load-balancers=vms82.liruilongs.github.io Ready <none> 45d v1.22.2 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,disktype=node1,kubernetes.io/arch=amd64,kubernetes.io/hostname=vms82.liruilongs.github.io,kubernetes.io/os=linuxvms83.liruilongs.github.io Ready <none> 45d v1.22.2 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,disktype=node2,kubernetes.io/arch=amd64,kubernetes.io/hostname=vms83.liruilongs.github.io,kubernetes.io/os=linux┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$特殊的内置标签node-role.kubernetes.io/control-plane=,node-role.kubernetes.io/master=,用于设置角色列roles
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl get nodeNAME STATUS ROLES AGE VERSIONvms81.liruilongs.github.io Ready control-plane,master 45d v1.22.2vms82.liruilongs.github.io Ready <none> 45d v1.22.2vms83.liruilongs.github.io Ready <none> 45d v1.22.2我们也可以做worker节点上设置
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl label nodes vms82.liruilongs.github.io node-role.kubernetes.io/worker1=node/vms82.liruilongs.github.io labeled┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl label nodes vms83.liruilongs.github.io node-role.kubernetes.io/worker2=node/vms83.liruilongs.github.io labeled┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl get nodeNAME STATUS ROLES AGE VERSIONvms81.liruilongs.github.io Ready control-plane,master 45d v1.22.2vms82.liruilongs.github.io Ready worker1 45d v1.22.2vms83.liruilongs.github.io Ready worker2 45d v1.22.2┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$选择器(nodeSelector)方式
在特定节点上运行pod
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get nodes -l disktype=node2NAME STATUS ROLES AGE VERSIONvms83.liruilongs.github.io Ready worker2 45d v1.22.2┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$vim pod-node2.yaml┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl apply -f pod-node2.yamlpod/podnode2 created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -owideNAMEREADY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESpodnode2 1/1 Running 0 13m 10.244.70.60 vms83.liruilongs.github.io <none> <none>pod-node2.yaml
apiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: podnode2 name: podnode2spec: nodeSelector: disktype: node2 containers: - image: nginx imagePullPolicy: IfNotPresent name: podnode2 resources: {} dnsPolicy: ClusterFirst restartPolicy: Alwaysstatus: {}指定节点名称(nodeName)的方式
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$vim pod-node1.yaml┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl apply -f pod-node1.yamlpod/podnode1 created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -owideNAMEREADY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESpodnode1 1/1 Running 0 36s 10.244.171.165 vms82.liruilongs.github.io <none> <none>podnode2 1/1 Running 0 13m 10.244.70.60 vms83.liruilongs.github.io <none> <none>pod-node1.yaml
apiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: podnode1 name: podnode1spec: nodeName: vms82.liruilongs.github.io containers: - image: nginx imagePullPolicy: IfNotPresent name: podnode1 resources: {} dnsPolicy: ClusterFirst restartPolicy: Alwaysstatus: {}当pod资源文件指定的节点标签,或者节点名不存在时，这个pod资源是无法创建成功的
主机亲和性
所谓主机亲和性，即在满足指定条件的节点上运行。分为硬策略(必须满足)，软策略(最好满足)
硬策略(requiredDuringSchedulingIgnoredDuringExecution)
pod-node-a.yaml
apiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: podnodea name: podnodeaspec: containers: - image: nginx imagePullPolicy: IfNotPresent name: podnodea resources: {} affinity: nodeAffinity: #主机亲和性 requiredDuringSchedulingIgnoredDuringExecution: #硬策略 nodeSelectorTerms: - matchExpressions: - key: kubernetes.io/hostname operator: In values: - vms85.liruilongs.github.io - vms84.liruilongs.github.io dnsPolicy: ClusterFirst restartPolicy: Alwaysstatus: {}条件不满足，所以 Pending
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl apply -f pod-node-a.yamlpod/podnodea created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get podsNAMEREADY STATUS RESTARTS AGEpodnodea 0/1 Pending 0 8s我梦修改一下
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$sed -i 's/vms84.liruilongs.github.io/vms83.liruilongs.github.io/' pod-node-a.yaml┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl apply -f pod-node-a.yamlpod/podnodea created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -owideNAMEREADY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESpodnodea 1/1 Running 0 13s 10.244.70.61 vms83.liruilongs.github.io <none> <none>┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$软策略(preferredDuringSchedulingIgnoredDuringExecution)
pod-node-a-r.yaml
apiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: podnodea name: podnodeaspec: containers: - image: nginx imagePullPolicy: IfNotPresent name: podnodea resources: {} affinity: nodeAffinity: #主机亲和性 preferredDuringSchedulingIgnoredDuringExecution: # 软策略 - weight: 2 preference: matchExpressions: - key: kubernetes.io/hostname operator: In values: - vms85.liruilongs.github.io - vms84.liruilongs.github.io dnsPolicy: ClusterFirst restartPolicy: Alwaysstatus: {}检查一下
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$vim pod-node-a-r.yaml┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl apply -f pod-node-a-r.yamlpod/podnodea created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -owideNAMEREADY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESpodnodea 1/1 Running 0 28s 10.244.70.62 vms83.liruilongs.github.io <none> <none>| 运算符 | 描述 |
|---|---|
| In | 包含自, 比如上面的硬亲和就包含env_role=dev、env_role=test两种标签 |
| NotIn | 和上面相反，凡是包含该标签的节点都不会匹配到 |
| Exists | 存在里面和In比较类似，凡是有某个标签的机器都会被选择出来。使用Exists的operator的话，values里面就不能写东西了。 |
| Gt | greater than的意思，表示凡是某个value大于设定的值的机器则会被选择出来。 |
| Lt | less than的意思，表示凡是某个value小于设定的值的机器则会被选择出来。 |
| DoesNotExists | 不存在该标签的节点 |
Annotations 的设置
Annotations 即注释，设置查看方式很简单
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl annotate nodes vms82.liruilongs.github.io "dest=这是一个工作节点"node/vms82.liruilongs.github.io annotated┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl describe nodes vms82.liruilongs.github.ioName: vms82.liruilongs.github.ioRoles:worker1Labels: beta.kubernetes.io/arch=amd64 beta.kubernetes.io/os=linux disktype=node1 kubernetes.io/arch=amd64 kubernetes.io/hostname=vms82.liruilongs.github.io kubernetes.io/os=linux node-role.kubernetes.io/worker1=Annotations: dest: 这是一个工作节点 kubeadm.alpha.kubernetes.io/cri-socket: /var/run/dockershim.sock node.alpha.kubernetes.io/ttl: 0 projectcalico.org/IPv4Address: 192.168.26.82/24 projectcalico.org/IPv4IPIPTunnelAddr: 10.244.171.128 volumes.kubernetes.io/controller-managed-attach-detach: true节点的coedon与drain
如果想把某个节点设置为不可用的话，可以对节点实施cordon或者drain
如果一个node被标记为cordon，新创建的pod不会被调度到此node上，已经调度上去的不会被移走
coedon用于节点的维护，当不希望再节点分配pod，那么可以使用coedon把节点标记为不可调度。
这里我们为了方便，创建一个Deployment控制器用去用于演示，关于Deployment，可以简单理解为他能保证你的pod保持在一定数量，当pod挂掉事，
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl create deployment nginx --image=nginx --dry-run=client -o yaml >nginx-dep.yaml┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$cp nginx-dep.yaml ./k8s-pod-create/nginx-dep.yaml┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$cd k8s-pod-create/┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$vim nginx-dep.yamlnginx-dep.yaml
apiVersion: apps/v1kind: Deploymentmetadata: creationTimestamp: null labels: app: nginx name: nginxspec: replicas: 3 selector: matchLabels: app: nginx strategy: {} template: metadata: creationTimestamp: null labels: app: nginx spec: containers: - image: nginx name: nginx imagePullPolicy: IfNotPresent resources: {}status: {}创建 deploy资源
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl apply -f nginx-dep.yamldeployment.apps/nginx created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -owideNAMEREADY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESnginx-7cf7d6dbc8-hx96s 1/1 Running 0 2m16s 10.244.171.167 vms82.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-wshxp 1/1 Running 0 2m16s 10.244.70.1 vms83.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-x78x4 1/1 Running 0 2m16s 10.244.70.63 vms83.liruilongs.github.io <none> <none>┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$节点的coedon
kubectl cordon vms83.liruilongs.github.io #标记不可用kubectl uncordon vms83.liruilongs.github.io #取消标记通过cordon把vms83.liruilongs.github.io标记为不可调度
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl cordon vms83.liruilongs.github.io #通过cordon把83标记为不可调度node/vms83.liruilongs.github.io cordoned查看节点状态，vms83.liruilongs.github.io变成SchedulingDisabled
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get nodesNAME STATUSROLES AGE VERSIONvms81.liruilongs.github.io Ready control-plane,master 48d v1.22.2vms82.liruilongs.github.io Ready worker1 48d v1.22.2vms83.liruilongs.github.io Ready,SchedulingDisabled worker2 48d v1.22.2修改deployment副本数量 --replicas=6
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl scale deployment nginx --replicas=6deployment.apps/nginx scaled新增的pod都调度到了vms82.liruilongs.github.io 节点
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -o wideNAMEREADY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESnginx-7cf7d6dbc8-2nmsj 1/1 Running 0 64s 10.244.171.170 vms82.liruilongs.github.io nginx-7cf7d6dbc8-chsrn 1/1 Running 0 63s 10.244.171.168 vms82.liruilongs.github.io nginx-7cf7d6dbc8-hx96s 1/1 Running 0 7m30s 10.244.171.167 vms82.liruilongs.github.io nginx-7cf7d6dbc8-lppbp 1/1 Running 0 63s 10.244.171.169 vms82.liruilongs.github.io nginx-7cf7d6dbc8-wshxp 1/1 Running 0 7m30s 10.244.70.1 vms83.liruilongs.github.io nginx-7cf7d6dbc8-x78x4 1/1 Running 0 7m30s 10.244.70.63 vms83.liruilongs.github.io ┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$把vms83.liruilongs.github.io节点上的Nginx都干掉，会发现新增pod都调度到了vms82.liruilongs.github.io
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl delete pod nginx-7cf7d6dbc8-wshxppod "nginx-7cf7d6dbc8-wshxp" deleted┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -o wideNAMEREADY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESnginx-7cf7d6dbc8-2nmsj 1/1 Running 0 2m42s 10.244.171.170 vms82.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-5hnc7 1/1 Running 0 10s 10.244.171.171 vms82.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-chsrn 1/1 Running 0 2m41s 10.244.171.168 vms82.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-hx96s 1/1 Running 0 9m8s 10.244.171.167 vms82.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-lppbp 1/1 Running 0 2m41s 10.244.171.169 vms82.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-x78x4 1/1 Running 0 9m8s 10.244.70.63 vms83.liruilongs.github.io <none> <none>┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl delete pod nginx-7cf7d6dbc8-x78x4pod "nginx-7cf7d6dbc8-x78x4" deleted┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -o wideNAMEREADY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESnginx-7cf7d6dbc8-2nmsj 1/1 Running 0 3m31s 10.244.171.170 vms82.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-5hnc7 1/1 Running 0 59s 10.244.171.171 vms82.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-chsrn 1/1 Running 0 3m30s 10.244.171.168 vms82.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-hx96s 1/1 Running 0 9m57s 10.244.171.167 vms82.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-lppbp 1/1 Running 0 3m30s 10.244.171.169 vms82.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-m8ltr 1/1 Running 0 30s 10.244.171.172 vms82.liruilongs.github.io <none> <none>通过 uncordon恢复节点vms83.liruilongs.github.io状态
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl uncordon vms83.liruilongs.github.io #恢复节点状态node/vms83.liruilongs.github.io uncordoned┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get nodesNAME STATUS ROLES AGE VERSIONvms81.liruilongs.github.io Ready control-plane,master 48d v1.22.2vms82.liruilongs.github.io Ready worker1 48d v1.22.2vms83.liruilongs.github.io Ready worker2 48d v1.22.2删除所有的pod
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl scale deployment nginx --replicas=0deployment.apps/nginx scaled┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -o wideNo resources found in liruilong-pod-create namespace.节点的为drain
如果一个节点被设置为drain，则此节点不再被调度pod，且此节点上已经运行的pod会被驱逐(evicted)到其他节点
drain包含两种状态：cordon不可被调度，evicted驱逐当前节点所以pod
kubectl drain vms83.liruilongs.github.io --ignore-daemonsetskubectl uncordon vms83.liruilongs.github.io 通过deployment添加4个nginx副本--replicas=4
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl scale deployment nginx --replicas=4deployment.apps/nginx scaled┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -o wide --one-outputNAMEREADY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESnginx-7cf7d6dbc8-2clnb 1/1 Running 0 22s 10.244.171.174 vms82.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-9p6g2 1/1 Running 0 22s 10.244.70.2 vms83.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-ptqxm 1/1 Running 0 22s 10.244.171.173 vms82.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-zmdqm 1/1 Running 0 22s 10.244.70.4 vms83.liruilongs.github.io <none> <none>添加一下污点 将节点vms82.liruilongs.github.io设置为drain
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl drain vms82.liruilongs.github.io --ignore-daemonsets --delete-emptydir-datanode/vms82.liruilongs.github.io cordonedWARNING: ignoring DaemonSet-managed Pods: kube-system/calico-node-ntm7v, kube-system/kube-proxy-nzm24evicting pod liruilong-pod-create/nginx-7cf7d6dbc8-ptqxmevicting pod kube-system/metrics-server-bcfb98c76-wxv5levicting pod liruilong-pod-create/nginx-7cf7d6dbc8-2clnbpod/nginx-7cf7d6dbc8-2clnb evictedpod/nginx-7cf7d6dbc8-ptqxm evictedpod/metrics-server-bcfb98c76-wxv5l evictednode/vms82.liruilongs.github.io evicted┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get nodesNAME STATUSROLES AGE VERSIONvms81.liruilongs.github.io Ready control-plane,master 48d v1.22.2vms82.liruilongs.github.io Ready,SchedulingDisabled worker1 48d v1.22.2vms83.liruilongs.github.io Ready worker2 48d v1.22.2查看节点调度，所有pod调度到了vms83.liruilongs.github.io这台机器
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -o wide --one-outputNAMEREADY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESnginx-7cf7d6dbc8-9p6g2 1/1 Running 0 4m20s 10.244.70.2 vms83.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-hkflr 1/1 Running 0 25s 10.244.70.5 vms83.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-qt48k 1/1 Running 0 26s 10.244.70.7 vms83.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-zmdqm 1/1 Running 0 4m20s 10.244.70.4 vms83.liruilongs.github.io <none> <none>┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$取消污点：kubectl uncordon vms82.liruilongs.github.io
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl uncordon vms82.liruilongs.github.ionode/vms82.liruilongs.github.io uncordoned┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$报错的情况
将节点vms82.liruilongs.github.io设置为drain
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl drain vms82.liruilongs.github.ionode/vms82.liruilongs.github.io cordonedDEPRECATED WARNING: Aborting the drain command in a list of nodes will be deprecated in v1.23.The new behavior will make the drain command go through all nodes even if one or more nodes failed during the drain.For now, users can try such experience via: --ignore-errorserror: unable to drain node "vms82.liruilongs.github.io", aborting command...There are pending nodes to be drained: vms82.liruilongs.github.iocannot delete DaemonSet-managed Pods (use --ignore-daemonsets to ignore): kube-system/calico-node-ntm7v, kube-system/kube-proxy-nzm24cannot delete Pods with local storage (use --delete-emptydir-data to override): kube-system/metrics-server-bcfb98c76-wxv5l┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get nodesNAME STATUSROLES AGE VERSIONvms81.liruilongs.github.io Ready control-plane,master 48d v1.22.2vms82.liruilongs.github.io Ready,SchedulingDisabled worker1 48d v1.22.2vms83.liruilongs.github.io Ready worker2 48d v1.22.2uncordon掉刚才的节点
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl uncordon vms82.liruilongs.github.ionode/vms82.liruilongs.github.io uncordoned┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get nodesNAME STATUS ROLES AGE VERSIONvms81.liruilongs.github.io Ready control-plane,master 48d v1.22.2vms82.liruilongs.github.io Ready worker1 48d v1.22.2vms83.liruilongs.github.io Ready worker2 48d v1.22.2节点taint(污点)及pod的tolerations(容忍污点)
给节点设置及删除taint，设置operator的值为Equal，以及设置operator的值为Exists
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$ansible master -m shell -a "kubectl describe nodes vms81.liruilongs.github.io | grep -E '(Roles|Taints)'"192.168.26.81 | CHANGED | rc=0 >>Roles:control-plane,masterTaints: node-role.kubernetes.io/master:NoSchedulemaster节点从来没有调度到pod，因为master节点设置了污点，如果想要在某个被设置了污点的机器调度pod，那么pod需要设置tolerations(容忍污点)才能够被运行。
taint（污点）的设置和查看
# 查看节点角色，和是否设置污点┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl describe nodes vms82.liruilongs.github.io | grep -E '(Roles|Taints)'Roles:worker1Taints: <none># 给 vms83.liruilongs.github.io节点设置污点，指定key为key83┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl describe nodes vms83.liruilongs.github.io | grep -E '(Roles|Taints)'Roles:worker2Taints: <none>┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl taint node vms83.liruilongs.github.io key83=:NoSchedulenode/vms83.liruilongs.github.io tainted┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl describe nodes vms83.liruilongs.github.io | grep -E '(Roles|Taints)' # 从新查看污点信息Roles:worker2Taints: key83:NoSchedule┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$重新通过deployment 创建pod，会发现pod都调度到82上面，因为83设置了污点
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl scale deployment nginx --replicas=0deployment.apps/nginx scaled┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl scale deployment nginx --replicas=4deployment.apps/nginx scaled┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -o wide --one-outputNAMEREADY STATUSRESTARTS AGE IPNODE NOMINATED NODE READINESS GATESnginx-7cf7d6dbc8-dhst5 0/1 ContainerCreating 0 12s <none> vms82.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-j6g25 0/1 ContainerCreating 0 12s <none> vms82.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-wpnhr 0/1 ContainerCreating 0 12s <none> vms82.liruilongs.github.io <none> <none>nginx-7cf7d6dbc8-zkww8 0/1 ContainerCreating 0 11s <none> vms82.liruilongs.github.io <none> <none>┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl delete deployment nginxdeployment.apps "nginx" deleted取消污点设置
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl taint node vms83.liruilongs.github.io key83-node/vms83.liruilongs.github.io untainted┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl describe nodes vms83.liruilongs.github.io | grep -E '(Roles|Taints)'Roles:worker2Taints: <none>┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$设置operator的值为Equal
如果需要在有污点的节点上运行pod，那么需要在定义pod的时候指定toleration属性
在设置节点taint的时候，如果value的值为不为空，在pod里的tolerations字段只能写Equal，不能写Exists,
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl taint nodes vms82.liruilongs.github.io key82=val82:NoSchedulenode/vms82.liruilongs.github.io tainted┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl describe nodes vms82.liruilongs.github.io | grep -E '(Roles|Taints)'Roles:worker1Taints: key82=val82:NoSchedule┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$设置operator的值为Exists
如果使用Exists的话，那么pod中不能写value
设置vms83.liruilongs.github.io 节点污点标记
┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl taint node vms83.liruilongs.github.io key83=:NoSchedulenode/vms83.liruilongs.github.io tainted┌──[root@vms81.liruilongs.github.io]-[~/ansible]└─$kubectl describe nodes vms83.liruilongs.github.io | grep -E '(Roles|Taints)'Roles:worker2Taints: key83:NoSchedule┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get nodes --show-labelsNAME STATUS ROLES AGE VERSION LABELSvms81.liruilongs.github.io Ready control-plane,master 48d v1.22.2 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=vms81.liruilongs.github.io,kubernetes.io/os=linux,node-role.kubernetes.io/control-plane=,node-role.kubernetes.io/master=,node.kubernetes.io/exclude-from-external-load-balancers=vms82.liruilongs.github.io Ready worker1 48d v1.22.2 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,disktype=node1,kubernetes.io/arch=amd64,kubernetes.io/hostname=vms82.liruilongs.github.io,kubernetes.io/os=linux,node-role.kubernetes.io/worker1=vms83.liruilongs.github.io Ready worker2 48d v1.22.2 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,disktype=node2,kubernetes.io/arch=amd64,kubernetes.io/hostname=vms83.liruilongs.github.io,kubernetes.io/os=linux,node-role.kubernetes.io/worker2=pod-taint.yaml
apiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: pod1 name: pod1spec: nodeSelector: disktype: node2 tolerations: - key: "key83" operator: "Exists" effect: "NoSchedule" containers: - image: nginx name: pod1 resources: {} dnsPolicy: ClusterFirst restartPolicy: Alwaysstatus: {}会发现节点调度到了有污点的vms83.liruilongs.github.io节点
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl apply -f pod-taint.yamlpod/pod1 created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -o wideNAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESpod1 1/1 Running 0 3m4s 10.244.70.8 vms83.liruilongs.github.io <none> <none>当然，value没有值也可以这样使用Equal
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$cp pod-taint.yaml pod-taint2.yaml┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$vim pod-taint2.yamlpod-taint2.yaml
apiVersion: v1kind: Podmetadata: creationTimestamp: null labels: run: pod1 name: pod1spec: nodeSelector: disktype: node2 tolerations: - key: "key83" operator: "Equal" value: "" effect: "NoSchedule" containers: - image: nginx name: pod1 resources: {} dnsPolicy: ClusterFirst restartPolicy: Alwaysstatus: {}会发现节点还是调度到了有污点的vms83.liruilongs.github.io节点
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl delete -f pod-taint.yamlpod "pod1" deleted┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl apply -f pod-taint2.yamlpod/pod1 created┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl get pods -o wideNAME READY STATUSRESTARTS AGE IPNODE NOMINATED NODE READINESS GATESpod1 0/1 ContainerCreating 0 8s <none> vms83.liruilongs.github.io <none> <none>┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl taint nodes vms83.liruilongs.github.io key83-node/vms83.liruilongs.github.io untainted┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$资源的文件 apiVersion 定义资源
┌──[root@vms81.liruilongs.github.io]-[~/ansible/k8s-pod-create]└─$kubectl api-resources书籍勘误：
P95:初始化容器代码片段修改交换分区相关内核参数为 10，代码片段下方描述里为 0。
P119:第三个代码块，按照书里描述应该是：
- key: "keyxx" operator: "Equal" value: "" effect: "NoSchedule"
