1、Pod容器组
可以把容器组（Pod）等同于某个特定应用和服务的：逻辑主机，其中包含一个或多个应用容器，这些容器相对紧密的耦合在一起，相互协调完成这个“逻辑主机”特定的工作。
1.1 Kubernetes的Pod
容器组（Pod）是Kubernetes的最小工作单位，一个Pod代表集群上正在运行的一个进程，Pod中的容器会作为一个整体被Master调度到一个Node上运行。
Pod为容器提供了两种共享资源：网络和存储
网络
每个Pod被分配一个独立的IP地址，Pod中的每个容器共享网络命名空间，包括IP地址和网络，Pod内的容器可以使用Localhost相互通信。
存储
Pod可以指定一组共享Volumes,Pod中的所有容器都可以访问共享Volumes，允许这些容器数据共享。
Volumes还用于Pod中的数据持久化，以防其中一个容器需要重新启动而丢失数据，当Kubernetes挂载Volume到Pod，本质上是将Volume挂载到Pod中的每一个容器。
1.2 查看Pod
kubectl get pods
查看Pod参数 | 说明 |
无参数 | 查看当前命名空间 |
--namespace kube-system | 查看kube-system命名空间 |
-A | 查看所有命名空间 |
# 在default的名字空间没有pod
[root@master ~]# kubectl get pods
No resources found in default namespace.
# 查看kube-system空间查看pod
[root@master ~]# kubectl get pods --namespace kube-system
NAME READY STATUS RESTARTS AGE
calico-kube-controllers-7cc8dd57d9-gc5pj 1/1 Running 0 26m
calico-kube-controllers-7cc8dd57d9-qzc2v 1/1 Terminating 0 98m
calico-node-74wx2 1/1 Running 1 9d
calico-node-759t9 1/1 Running 0 94m
calico-node-8qjzg 1/1 Running 1 9d
calico-node-jg4ld 1/1 Running 1 9d
coredns-545d6fc579-cv67b 1/1 Running 0 26m
coredns-545d6fc579-mt5v5 1/1 Running 1 9d
coredns-545d6fc579-sw8bz 1/1 Terminating 0 98m
etcd-master 1/1 Running 3 9d
kube-apiserver-master 1/1 Running 4 9d
kube-controller-manager-master 1/1 Running 3 9d
kube-proxy-5kdvd 1/1 Running 1 9d
kube-proxy-5mhh9 1/1 Running 0 94m
kube-proxy-c54vr 1/1 Running 3 9d
kube-proxy-mzrqv 1/1 Running 1 9d
kube-scheduler-master 1/1 Running 3 9d
metrics-server-bcfb98c76-5v794 1/1 Running 0 41m1.3 创建Pod
kubectl run 名字 --image 镜像
创建Pod参数 | 说明 |
--labels | 标签=值 |
--env | 变量名=值 |
--port | 端口号 |
--image-pull-policy | 镜像下载策略 |
# 创建一个名为pod1的pod，使用nginx镜像
[root@master ~]# kubectl run pod1 --image=nginx
pod/pod1 created
# 查看pod状态
[root@master ~]# kubectl get pod --namespace default -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
pod1 1/1 Running 0 40s 10.244.104.3 node2 <none> <none>1.4 生成创建pod文件
yaml文件子级和父级之间缩进2空格，子级的第一个位置以'-'开头
[root@master ~]# kubectl run pod1 --image=nginx --dry-run=client -o yaml > pod1.yaml
[root@master ~]# cat pod1.yaml
apiVersion: v1
kind: Pod
metadata:
creationTimestamp: null
labels:
run: pod1
name: pod1
spec:
containers:
- image: nginx
name: pod1
resources: {}
dnsPolicy: ClusterFirst
restartPolicy: Always
status: {}在pod执行命令，然后休眠10秒
[root@master ~]# kubectl run pod2 --image=nginx --image-pull-policy IfNotPresent --dry-run=client -o yaml -- sh -c 'echo hello ; sleep 10' > pod2.yaml
[root@master ~]# cat pod2.yaml
apiVersion: v1
kind: Pod
metadata:
creationTimestamp: null
labels:
run: pod2
name: pod2
spec:
containers:
- args:
- sh
- -c
- echo hello ; sleep 10
image: nginx
imagePullPolicy: IfNotPresent
name: pod2
resources: {}
dnsPolicy: ClusterFirst
restartPolicy: Always
status: {}1.5 根据编排文件创建pod
kubectl apply -f 文件名
[root@master ~]# kubectl apply -f pod2.yaml
pod/pod2 created1.6 查看Pod状态
kubectl get pods
查看pod状态参数 | 说明 |
--show-labels | 显示标签 |
-l run=pod1 | 查看指定pod运行状态 |
-o wide | 查看详细信息 |
显示标签
[root@master ~]# kubectl get pods --show-labels
NAME READY STATUS RESTARTS AGE LABELS
pod1 1/1 Running 0 47m run=pod1
pod2 0/1 CrashLoopBackOff 3 101s run=pod2查看指定pod运行状态
[root@master ~]# kubectl get pods -l run=pod1
NAME READY STATUS RESTARTS AGE
pod1 1/1 Running 0 50m
[root@master ~]# kubectl get pods -l run=pod2
NAME READY STATUS RESTARTS AGE
pod2 0/1 CrashLoopBackOff 5 4m19s查看pod详细信息
[root@master ~]# kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
pod1 1/1 Running 0 53m 10.244.104.3 node2 <none> <none>
pod2 0/1 CrashLoopBackOff 6 8m 10.244.104.5 node2 <none> <none>1.7 删除pod
kubectl delete pod pod名
# 删除pod2
[root@master ~]# kubectl delete pod pod2
pod "pod2" deleted2、Pod基本操作
2.1 pod内执行命令
命令格式：kubectl exec pod 名字 -- 命令
# 在pod1下执行ls命令
[root@master ~]# kubectl exec pod1 -- ls /usr/share/nginx/html
50x.html
index.html2.2 复制操作
主机文件 --> 容器：kubectl cp 要复制文件 pod名：复制路径
# 将/etc/hosts文件复制到pod中
[root@master ~]# kubectl cp /etc/hosts pod1:/usr/share/nginx/html
[root@master ~]# kubectl exec pod1 -- ls /usr/share/nginx/html
50x.html
hosts
index.html容器文件 --> 主机：kubectl cp pod名：复制路径 文件名
[root@master ~]# kubectl cp pod1:/usr/share/nginx/html ./html/
tar: Removing leading `/' from member names
[root@master ~]# ls html/
50x.html hosts index.html2.3 获取命令行
操作类似docker
[root@master ~]# kubectl exec -it pod1 -- bash
root@pod1:/#2.4 查看pod详细信息
kubectl describe pod pod1
[root@master ~]# kubectl describe pod pod1
Name: pod1
Namespace: default
Priority: 0
Node: node2/192.168.0.102
Start Time: Sun, 25 Jun 2023 14:01:40 +0800
Labels: run=pod1
Annotations: cni.projectcalico.org/containerID: d1f22fde386dbb724ad27aeb0a819c72343e7e70079699b832fd864eea886c6b
cni.projectcalico.org/podIP: 10.244.104.3/32
cni.projectcalico.org/podIPs: 10.244.104.3/32
Status: Running
IP: 10.244.104.3
IPs:
IP: 10.244.104.3
Containers:
pod1:
Container ID: docker://e2c5e304d86e348fa5511826749a32325fc70e09d695247bc34a31deb10728d2
Image: nginx
Image ID: docker-pullable://nginx@sha256:0d17b565c37bcbd895e9d92315a05c1c3c9a29f762b011a10c54a66cd53c9b31
Port: <none>
Host Port: <none>
State: Running
Started: Sun, 25 Jun 2023 14:01:47 +0800
Ready: True
Restart Count: 0
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-pbv9z (ro)
Conditions:
Type Status
Initialized True
Ready True
ContainersReady True
PodScheduled True
Volumes:
kube-api-access-pbv9z:
Type: Projected (a volume that contains injected data from multiple sources)
TokenExpirationSeconds: 3607
ConfigMapName: kube-root-ca.crt
ConfigMapOptional: <nil>
DownwardAPI: true
QoS Class: BestEffort
Node-Selectors: <none>
Tolerations: node.kubernetes.io/not-ready:NoExecute op=Exists for 300s
node.kubernetes.io/unreachable:NoExecute op=Exists for 300s
Events: <none>2.5 一个pod运行多容器
2.5.1 编排文件
# 修改pod生成文件，运行两个nginx容器
apiVersion: v1
kind: Pod
metadata:
creationTimestamp: null
labels:
run: pod2
name: pod2
spec:
containers:
- name: c1
image: nginx
# 优先拉取本地镜像
imagePullPolicy: IfNotPresent
command: ['sh','-c','echo hello;','sleep 10']
- name: c2
image: nginx
imagePullPolicy: IfNotPresent
resources: {}
dnsPolicy: ClusterFirst
restartPolicy: Always
status: {}其中command命令等价于
- args:
- sh
- -c
- echo hello;
- sleep 102.5.2 创建pod
[root@master ~]# kubectl apply -f pod2.yaml
pod/pod2 created2.5.3 进入某个容器
[root@master ~]# kubectl exec -it pod2 -c c2 -- bash
root@pod2:/#2.6 查看pod日志
查看方式：kubectl logs pod名称
# 单个容器使用kubectl logs pod
[root@master ~]# kubectl logs pod1
/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.sh
10-listen-on-ipv6-by-default.sh: info: Getting the checksum of /etc/nginx/conf.d/default.conf
10-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 up
2023/06/25 06:01:47 [notice] 1#1: using the "epoll" event method
2023/06/25 06:01:47 [notice] 1#1: nginx/1.21.5
2023/06/25 06:01:47 [notice] 1#1: built by gcc 10.2.1 20210110 (Debian 10.2.1-6)
2023/06/25 06:01:47 [notice] 1#1: OS: Linux 5.14.0-284.11.1.el9_2.x86_64
2023/06/25 06:01:47 [notice] 1#1: getrlimit(RLIMIT_NOFILE): 1073741816:1073741816
2023/06/25 06:01:47 [notice] 1#1: start worker processes
2023/06/25 06:01:47 [notice] 1#1: start worker process 31
2023/06/25 06:01:47 [notice] 1#1: start worker process 32
2023/06/25 06:01:47 [notice] 1#1: start worker process 33
2023/06/25 06:01:47 [notice] 1#1: start worker process 34
# 多个容器使用kubectl logs pod名称 -c 内部容器名称
[root@master ~]# kubectl logs pod2 -c c1
hello
[root@master ~]# kubectl logs pod2 -c c2
/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.sh
10-listen-on-ipv6-by-default.sh: info: Getting the checksum of /etc/nginx/conf.d/default.conf
10-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 up
2023/06/25 10:32:14 [notice] 1#1: using the "epoll" event method
2023/06/25 10:32:14 [notice] 1#1: nginx/1.21.5
2023/06/25 10:32:14 [notice] 1#1: built by gcc 10.2.1 20210110 (Debian 10.2.1-6)
2023/06/25 10:32:14 [notice] 1#1: OS: Linux 5.14.0-284.11.1.el9_2.x86_64
2023/06/25 10:32:14 [notice] 1#1: getrlimit(RLIMIT_NOFILE): 1073741816:1073741816
2023/06/25 10:32:14 [notice] 1#1: start worker processes
2023/06/25 10:32:14 [notice] 1#1: start worker process 31
2023/06/25 10:32:14 [notice] 1#1: start worker process 32
2023/06/25 10:32:14 [notice] 1#1: start worker process 33
2023/06/25 10:32:14 [notice] 1#1: start worker process 342.7 指定pod放置位置
通过给节点增加标签，指定pod在特定节点上运行，nodeSelector选项，可以指定pod在期望节点上运行
# 查看所有节点标签
kubectl get nodes --show-labels
# 查看特定节点标签
kubectl get nodes node1 --show-labels
# 查看节点详细信息
kubectl describe nodes node1设置节点标签
[root@master ~]# kubectl label node node1 diskxx=ssdxx
node/node1 labeled
# 验证
[root@master ~]# kubectl get node node1 --show-labels
NAME STATUS ROLES AGE VERSION LABELS
node1 Ready <none> 10d v1.21.1 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,diskxx=ssdxx,kubernetes.io/arch=amd64,kubernetes.io/hostname=node1,kubernetes.io/os=linux取消节点某个标签
[root@master ~]# kubectl label node node1 diskxx-
node/node1 labeled编辑配置文件
[root@master ~]# cat pod3.yaml
apiVersion: v1
kind: Pod
metadata:
creationTimestamp: null
labels:
run: pod3
name: pod3
spec:
nodeSelector:
diskxx: ssdxx
containers:
- image: nginx
imagePullPolicy: IfNotPresent
name: pod3
resources: {}
imagePullPolicy: IfNotPresent
dnsPolicy: ClusterFirst
restartPolicy: Always
status: {}生成容器
[root@master ~]# kubectl apply -f pod3.yaml
pod/podlabel created验证是否放置在node1下
[root@master ~]# kubectl describe pod pod3 | grep -i node
Node: node1/192.168.0.101
Node-Selectors: diskxx=ssdxx
Tolerations: node.kubernetes.io/not-ready:NoExecute op=Exists for 300s
node.kubernetes.io/unreachable:NoExecute op=Exists for 300s
Normal Scheduled 84s default-scheduler Successfully assigned default/pod3 to node13、注释Annotations
可以使用Labels或Annotations将元数据附加到Kubernetes对象，标签可用于选择对象并查找满足某些条件的对象集合。相比之下，Annotations不用于标识和选择对象。Annotations中的元数据可以使small或large，structured或unstructured，并且可以包含标签不允许使用的字符。
3.1 Annotations格式
"annotations": {
"key1" : "value1" ,
"key2" : "value2"
}以下是Annotations中记录信息的一些例子：
- 构件、发布的镜像信息，如时间戳，发行ID、GIT分支，PR编号，镜像哈希值和Registry地址
- 一些日志记录、监视、分析或audit repositories
- 一些工具信息：名称、版本、构件信息等
- 用户或工具/系统来源信息，例如来自其他生态系统组件对象的URL
- 负责人的电话/座机，或一些信息目录
注意：Annotations不会被Kubernetes直接使用，其主要目的是方便用户阅读查找。
3.2 查看Annotations属性
[root@master ~]# kubectl describe pod pod3
Name: pod3
Namespace: default
Priority: 0
Node: node1/192.168.0.101
Start Time: Sun, 25 Jun 2023 20:45:39 +0800
Labels: run=pod3
Annotations: cni.projectcalico.org/containerID: 45b93c4d6787cadaca31f3a977aab8a72835a946106234996921c5209469957e
cni.projectcalico.org/podIP: 10.244.166.130/32
cni.projectcalico.org/podIPs: 10.244.166.130/32
Status: Running
...3.3 添加Annotations属性
[root@master ~]# kubectl annotate nodes node1 name=node1
node/node1 annotated3.4 删除Annotations属性
[root@master ~]# kubectl annotate nodes node1 name-
node/node1 annotated3.5 查看Annotations属性
[root@master ~]# kubectl describe nodes node1 | grep Annotations -A 5
Annotations: kubeadm.alpha.kubernetes.io/cri-socket: /var/run/dockershim.sock
name: node1
node.alpha.kubernetes.io/ttl: 0
projectcalico.org/IPv4Address: 192.168.0.101/24
projectcalico.org/IPv4IPIPTunnelAddr: 10.244.166.128
volumes.kubernetes.io/controller-managed-attach-detach: true4、节点的cordon与drain
cordon：标志Node不可调度但不影响其上正在运行的Pod，通常集群在升级维护时很常用
drain：通过驱逐需要维护节点的pod，让该节点上的pod在其他节点运行，并标记警戒线
4.1 创建deployment
创建deployment类型yaml文件
kubectl create deployment nginx --image=nginx --dry-run=client -o yaml > d1.yaml编辑yaml文件，副本数改为9(replicas:9)
apiVersion: apps/v1
kind: Deployment
metadata:
creationTimestamp: null
labels:
app: nginx
name: nginx
spec:
replicas: 9
selector:
matchLabels:
app: nginx
strategy: {}
template:
metadata:
creationTimestamp: null
labels:
app: nginx
spec:
containers:
- image: nginx
name: nginx
resources: {}
status: {}执行deployment文件，此时发现有9个pod已经运行，每个node上分别运行3个
[root@master ~]# kubectl apply -f d1.yaml
[root@master ~]# kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE
nginx-6799fc88d8-5vtl7 1/1 Running 0 70s 10.244.135.4 node3
nginx-6799fc88d8-cmwj8 1/1 Running 0 70s 10.244.166.138 node1
nginx-6799fc88d8-ctzqm 1/1 Running 0 70s 10.244.166.139 node1
nginx-6799fc88d8-dwdh6 1/1 Running 0 70s 10.244.104.4 node2
nginx-6799fc88d8-msjlp 1/1 Running 0 70s 10.244.135.5 node3
nginx-6799fc88d8-qwzgq 1/1 Running 0 70s 10.244.166.140 node1
nginx-6799fc88d8-rqsn5 1/1 Running 0 70s 10.244.135.3 node3
nginx-6799fc88d8-vnv2w 1/1 Running 0 70s 10.244.104.5 node2
nginx-6799fc88d8-xmzkq 1/1 Running 0 70s 10.244.104.6 node24.2 设置cordon
设置node2为cordon，拉起警戒线，该节点进入不可调度状态
[root@master ~]# kubectl cordon node2
node/node2 cordoned查看节点状态信息
[root@master ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
master Ready control-plane,master 3d16h v1.21.1
node1 Ready <none> 3d16h v1.21.1
node2 Ready,SchedulingDisabled <none> 3d16h v1.21.1
node3 Ready <none> 3d16h v1.21.14.3 横向扩展副本数
通过命令设置副本数为12
kubectl scale deployment nginx --replicas=12查看pod状态
# 此时node2已经不接受新的pod
[root@master ~]# kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE
nginx-6799fc88d8-5vtl7 1/1 Running 0 30m 10.244.135.4 node3
nginx-6799fc88d8-cmwj8 1/1 Running 0 30m 10.244.166.138 node1
nginx-6799fc88d8-ctzqm 1/1 Running 0 30m 10.244.166.139 node1
nginx-6799fc88d8-dwdh6 1/1 Running 0 30m 10.244.104.4 node2
nginx-6799fc88d8-jsfxq 1/1 Running 0 65s 10.244.135.6 node3
nginx-6799fc88d8-msjlp 1/1 Running 0 30m 10.244.135.5 node3
nginx-6799fc88d8-mt25q 1/1 Running 0 65s 10.244.135.7 node3
nginx-6799fc88d8-np2pr 1/1 Running 0 65s 10.244.166.141 node1
nginx-6799fc88d8-qwzgq 1/1 Running 0 30m 10.244.166.140 node1
nginx-6799fc88d8-rqsn5 1/1 Running 0 30m 10.244.135.3 node3
nginx-6799fc88d8-vnv2w 1/1 Running 0 30m 10.244.104.5 node2
nginx-6799fc88d8-xmzkq 1/1 Running 0 30m 10.244.104.6 node2删除node2剩余3个pod
[root@master ~]# kubectl get pods -o wide | grep node2
nginx-6799fc88d8-dwdh6 1/1 Running 0 31m 10.244.104.4 node2 <none> <none>
nginx-6799fc88d8-vnv2w 1/1 Running 0 31m 10.244.104.5 node2 <none> <none>
nginx-6799fc88d8-xmzkq 1/1 Running 0 31m 10.244.104.6 node2 <none> <none>
[root@master ~]# kubectl delete pod nginx-6799fc88d8-dwdh6 nginx-6799fc88d8-vnv2w nginx-6799fc88d8-xmzkq
pod "nginx-6799fc88d8-dwdh6" deleted
pod "nginx-6799fc88d8-vnv2w" deleted
pod "nginx-6799fc88d8-xmzkq" deleted此时新的pod已经分配到node1和node3上
[root@master ~]# kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE
nginx-6799fc88d8-5vtl7 1/1 Running 0 32m 10.244.135.4 node3
nginx-6799fc88d8-6dtvp 1/1 Running 0 59s 10.244.166.143 node1
nginx-6799fc88d8-9bxxw 1/1 Running 0 59s 10.244.135.8 node3
nginx-6799fc88d8-cmwj8 1/1 Running 0 32m 10.244.166.138 node1
nginx-6799fc88d8-ctzqm 1/1 Running 0 32m 10.244.166.139 node1
nginx-6799fc88d8-hnm62 1/1 Running 0 59s 10.244.166.142 node1
nginx-6799fc88d8-jsfxq 1/1 Running 0 3m35s 10.244.135.6 node3
nginx-6799fc88d8-msjlp 1/1 Running 0 32m 10.244.135.5 node3
nginx-6799fc88d8-mt25q 1/1 Running 0 3m35s 10.244.135.7 node3
nginx-6799fc88d8-np2pr 1/1 Running 0 3m35s 10.244.166.141 node1
nginx-6799fc88d8-qwzgq 1/1 Running 0 32m 10.244.166.140 node1
nginx-6799fc88d8-rqsn5 1/1 Running 0 32m 10.244.135.3 node34.4 恢复cordon
[root@master ~]# kubectl uncordon node2
node/node2 uncordoned4.5 节点的drain
通过驱逐需要维护节点的pod，让该节点上的pod在其他节点运行，并标记警戒线
# 将node1设置为drain
kubectl drain node1 --ignore-daemonsets --delete-emptydir-data查看节点状态
[root@master ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
master Ready control-plane,master 3d17h v1.21.1
node1 Ready,SchedulingDisabled <none> 3d16h v1.21.1
node2 Ready <none> 3d16h v1.21.1
node3 Ready <none> 3d16h v1.21.1查看pod
[root@master ~]# kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE
nginx-6799fc88d8-5vtl7 1/1 Running 0 41m 10.244.135.4 node3
nginx-6799fc88d8-88wpm 1/1 Running 0 98s 10.244.104.12 node2
nginx-6799fc88d8-89kr6 1/1 Running 0 98s 10.244.104.7 node2
nginx-6799fc88d8-9bxxw 1/1 Running 0 9m36s 10.244.135.8 node3
nginx-6799fc88d8-jsfxq 1/1 Running 0 12m 10.244.135.6 node3
nginx-6799fc88d8-kxqc6 1/1 Running 0 98s 10.244.104.13 node2
nginx-6799fc88d8-msjlp 1/1 Running 0 41m 10.244.135.5 node3
nginx-6799fc88d8-mt25q 1/1 Running 0 12m 10.244.135.7 node3
nginx-6799fc88d8-n876z 1/1 Running 0 98s 10.244.104.11 node2
nginx-6799fc88d8-nf726 1/1 Running 0 98s 10.244.104.10 node2
nginx-6799fc88d8-rqsn5 1/1 Running 0 41m 10.244.135.3 node3
nginx-6799fc88d8-zsd72 1/1 Running 0 98s 10.244.104.9 node2维护结束后，修改节点状态
[root@master ~]# kubectl uncordon node1
node/node1 uncordoned
[root@master ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
master Ready control-plane,master 3d17h v1.21.1
node1 Ready <none> 3d16h v1.21.1
node2 Ready <none> 3d16h v1.21.1
node3 Ready <none> 3d16h v1.21.15、节点Taint及pod的tolerations
Taints（污点）和tolerations（污点容忍）用于保证Pod不被调度到不合适的Node上
- Taint应用于Node上
- 而toleration则应用于Pod上（Toleration是可选的）
5.1 查看节点taints设置
[root@master ~]# kubectl describe nodes node1 | grep -Ei 'roles|taints'
Roles: <none>
Taints: <none>5.2 配置节点taint（污点）
常见的污点设置一般为NoSchedule
[root@master ~]# kubectl taint nodes node1 keyxx=valuexx:NoSchedule
node/node1 tainted
[root@master ~]# kubectl describe nodes node1 | grep -Ei 'roles|taints'
Roles: <none>
Taints: keyxx=valuexx:NoSchedule5.3 生成pod
[root@master ~]# kubectl apply -f d1.yaml
deployment.apps/nginx created5.4 查看pod具体位置
由于已经给node1定义污点，故pod不会主动放置在node1上
[root@master ~]# kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE
nginx-6799fc88d8-5jtgh 0/1 ContainerCreating 0 7s <none> node3
nginx-6799fc88d8-62drm 0/1 ContainerCreating 0 7s <none> node2
nginx-6799fc88d8-mtlxt 0/1 ContainerCreating 0 7s <none> node3
nginx-6799fc88d8-p8md8 0/1 ContainerCreating 0 7s <none> node2
nginx-6799fc88d8-snn46 0/1 ContainerCreating 0 7s <none> node2
nginx-6799fc88d8-xxs56 0/1 ContainerCreating 0 7s <none> node2
nginx-6799fc88d8-z6jms 0/1 ContainerCreating 0 7s <none> node3
nginx-6799fc88d8-zbgts 0/1 ContainerCreating 0 7s <none> node3
nginx-6799fc88d8-zz67w 0/1 ContainerCreating 0 7s <none> node35.5 删除pod
[root@master ~]# kubectl delete deployments.apps nginx
deployment.apps "nginx" deleted5.6 让pod在taint节点运行
# 生成编排文件
kubectl run podtaint --image=nginx --dry-run=client -o yaml > podtaint.yaml
# 给node1打上标签（Label）
kubectl label node node1 diskxx=ssdxx配置编排文件如下
[root@master ~]# cat podtaint.yaml
apiVersion: v1
kind: Pod
metadata:
creationTimestamp: null
labels:
run: podtaint
name: podtaint
spec:
# 标签选择器
nodeSelector:
diskxx: ssdxx
# 配置tolerations，指定key、value和NoSchedule
tolerations:
- key: keyxx
operator: Equal
value: valuexx
effect: NoSchedule
containers:
- image: nginx
name: podtaint
resources: {}
dnsPolicy: ClusterFirst
restartPolicy: Always
status: {}5.7 查看Pod运行状态
此时pod已经顺利在node1上运行
[root@master ~]# kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
podtaint 1/1 Running 0 19s 10.244.166.145 node1 <none> <none>
