Kubernetes集群Node管理

  • 一、查看集群信息
  • 二、查看节点信息
  • 2.1 查看集群节点信息
  • 2.2 查看集群节点详细信息
  • 2.3 查看节点描述详细信息
  • 三、worker node节点管理集群
  • 四、节点标签(label)
  • 4.1 查看节点标签信息
  • 4.2 设置节点标签信息
  • 4.2.1 设置节点标签
  • 4.2.2 查看所有节点带region的标签
  • 4.3 多维度标签
  • 4.3.1 设置多维度标签
  • 4.3.2 显示节点的相应标签
  • 4.3.3 查找`region=huanai`的节点
  • 4.3.4 标签的修改
  • 4.3.5 标签的删除
  • 4.3.6 标签选择器


一、查看集群信息

[root@k8s-master01 ~]# kubectl cluster-info
Kubernetes control plane is running at https://192.168.10.100:6443
CoreDNS is running at https://192.168.10.100:6443/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy
To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'.

二、查看节点信息

2.1 查看集群节点信息

[root@k8s-master01 ~]# kubectl get nodes
NAME           STATUS   ROLES    AGE   VERSION
k8s-master01   Ready    <none>   36d   v1.21.10
k8s-master02   Ready    <none>   36d   v1.21.10
k8s-master03   Ready    <none>   36d   v1.21.10
k8s-worker02   Ready    <none>   36d   v1.21.10

2.2 查看集群节点详细信息

[root@k8s-master01 ~]# kubectl get nodes -owide
NAME           STATUS   ROLES    AGE   VERSION    INTERNAL-IP      EXTERNAL-IP   OS-IMAGE                KERNEL-VERSION              CONTAINER-RUNTIME
k8s-master01   Ready    <none>   36d   v1.21.10   192.168.10.101   <none>        CentOS Linux 7 (Core)   6.1.0-1.el7.elrepo.x86_64   docker://20.10.22
k8s-master02   Ready    <none>   36d   v1.21.10   192.168.10.102   <none>        CentOS Linux 7 (Core)   6.1.0-1.el7.elrepo.x86_64   docker://20.10.22
k8s-master03   Ready    <none>   36d   v1.21.10   192.168.10.103   <none>        CentOS Linux 7 (Core)   6.1.0-1.el7.elrepo.x86_64   docker://20.10.22
k8s-worker02   Ready    <none>   36d   v1.21.10   192.168.10.104   <none>        CentOS Linux 7 (Core)   6.1.1-1.el7.elrepo.x86_64   docker://20.10.22

2.3 查看节点描述详细信息

[root@k8s-master01 ~]# kubectl describe nodes k8s-master01
Name:               k8s-master01
Roles:              <none>
Labels:             beta.kubernetes.io/arch=amd64
                    beta.kubernetes.io/os=linux
                    kubernetes.io/arch=amd64
                    kubernetes.io/hostname=k8s-master01
                    kubernetes.io/os=linux
Annotations:        node.alpha.kubernetes.io/ttl: 0
                    projectcalico.org/IPv4Address: 192.168.10.101/24
                    projectcalico.org/IPv4IPIPTunnelAddr: 10.244.32.128
                    volumes.kubernetes.io/controller-managed-attach-detach: true
CreationTimestamp:  Sat, 24 Dec 2022 23:45:43 +0800
Taints:             <none>
Unschedulable:      false
Lease:
  HolderIdentity:  k8s-master01
  AcquireTime:     <unset>
  RenewTime:       Mon, 30 Jan 2023 11:03:00 +0800
Conditions:
  Type                 Status  LastHeartbeatTime                 LastTransitionTime                Reason                       Message
  ----                 ------  -----------------                 ------------------                ------                       -------
  NetworkUnavailable   False   Sun, 29 Jan 2023 10:12:40 +0800   Sun, 29 Jan 2023 10:12:40 +0800   CalicoIsUp                   Calico is running on this node
  MemoryPressure       False   Mon, 30 Jan 2023 11:00:34 +0800   Sat, 24 Dec 2022 23:45:42 +0800   KubeletHasSufficientMemory   kubelet has sufficient memory available
  DiskPressure         False   Mon, 30 Jan 2023 11:00:34 +0800   Sat, 24 Dec 2022 23:45:42 +0800   KubeletHasNoDiskPressure     kubelet has no disk pressure
  PIDPressure          False   Mon, 30 Jan 2023 11:00:34 +0800   Sat, 24 Dec 2022 23:45:42 +0800   KubeletHasSufficientPID      kubelet has sufficient PID available
  Ready                True    Mon, 30 Jan 2023 11:00:34 +0800   Sun, 25 Dec 2022 00:06:35 +0800   KubeletReady                 kubelet is posting ready status
Addresses:
  InternalIP:  192.168.10.101
  Hostname:    k8s-master01
Capacity:
  cpu:                2
  ephemeral-storage:  19466Mi
  hugepages-1Gi:      0
  hugepages-2Mi:      0
  memory:             3995080Ki
  pods:               110
Allocatable:
  cpu:                2
  ephemeral-storage:  18370422344
  hugepages-1Gi:      0
  hugepages-2Mi:      0
  memory:             3892680Ki
  pods:               110
System Info:
  Machine ID:                 0e0a3ea7d11c4165b5eb28435792ad47
  System UUID:                d3794d56-6573-8633-b1d0-456a80d8ee9a
  Boot ID:                    09607e08-716a-4834-847b-534c12d3e5de
  Kernel Version:             6.1.0-1.el7.elrepo.x86_64
  OS Image:                   CentOS Linux 7 (Core)
  Operating System:           linux
  Architecture:               amd64
  Container Runtime Version:  docker://20.10.22
  Kubelet Version:            v1.21.10
  Kube-Proxy Version:         v1.21.10
PodCIDR:                      10.244.0.0/24
PodCIDRs:                     10.244.0.0/24
Non-terminated Pods:          (2 in total)
  Namespace                   Name                                         CPU Requests  CPU Limits  Memory Requests  Memory Limits  Age
  ---------                   ----                                         ------------  ----------  ---------------  -------------  ---
  kube-system                 calico-node-d5qw7                            250m (12%)    0 (0%)      0 (0%)           0 (0%)         36d
  kubernetes-dashboard        dashboard-metrics-scraper-c45b7869d-9c8jj    0 (0%)        0 (0%)      0 (0%)           0 (0%)         35d
Allocated resources:
  (Total limits may be over 100 percent, i.e., overcommitted.)
  Resource           Requests    Limits
  --------           --------    ------
  cpu                250m (12%)  0 (0%)
  memory             0 (0%)      0 (0%)
  ephemeral-storage  0 (0%)      0 (0%)
  hugepages-1Gi      0 (0%)      0 (0%)
  hugepages-2Mi      0 (0%)      0 (0%)
Events:              <none>

三、worker node节点管理集群

  • 如果是kubeasz安装,所有节点(包括master与node)都已经可以对集群进行管理
  • 如果是kubeadm安装,在node节点上管理时会报如下错误
[root@k8s-worker1 ~]# kubectl get nodes
The connection to the server localhost:8080 was refused - did you specify the right host or port?

把master上的管理文件/etc/kubernetes/admin.conf拷贝到node节点的$HOME/.kube/config就可以让node节点也可以实现kubectl命令管理

在node节点的用户家目录创建.kube目录

[root@k8s-worker02 ~]# mkdir /root/.kube

2, 在master节点做如下操作

[root@k8s-worker02 ~]# scp /etc/kubernetes/admin.conf node1:/root/.kube/config

3, 在worker node节点验证

[root@k8s-worker02 ~]# kubectl get nodes
NAME          STATUS   ROLES    AGE     VERSION
k8s-master01   Ready    <none>   2d20h   v1.21.10
k8s-master02   Ready    <none>   2d20h   v1.21.10
k8s-master03   Ready    <none>   2d20h   v1.21.10
k8s-worker02   Ready    <none>   2d20h   v1.21.10

四、节点标签(label)

  • k8s集群如果由大量节点组成,可将节点打上对应的标签,然后通过标签进行筛选及查看,更好的进行资源对象的相关选择与匹配

4.1 查看节点标签信息

[root@k8s-master01 ~]# kubectl get nodes --show-labels 
NAME           STATUS   ROLES    AGE   VERSION    LABELS
k8s-master01   Ready    <none>   36d   v1.21.10   beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=k8s-master01,kubernetes.io/os=linux
k8s-master02   Ready    <none>   36d   v1.21.10   beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,env=test1,kubernetes.io/arch=amd64,kubernetes.io/hostname=k8s-master02,kubernetes.io/os=linux
k8s-master03   Ready    <none>   36d   v1.21.10   beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,bussiness=ad,env=test2,kubernetes.io/arch=amd64,kubernetes.io/hostname=k8s-master03,kubernetes.io/os=linux,zone=A
k8s-worker02   Ready    <none>   36d   v1.21.10   beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=k8s-worker02,kubernetes.io/os=linux

4.2 设置节点标签信息

4.2.1 设置节点标签

为节点k8s-worker1打一个region=huanai 的标签

[root@k8s-master01 ~]# kubectl label node k8s-worker01 region=huanai
node/k8s-worker01 labeled

4.2.2 查看所有节点带region的标签

[root@k8s-master01 ~]# kubectl get nodes -L region
NAME          STATUS   ROLES    AGE     VERSION    REGION
k8s-master01   Ready    <none>   2d21h   v1.21.10
k8s-master02   Ready    <none>   2d21h   v1.21.10
k8s-master03   Ready    <none>   2d21h   v1.21.10
k8s-worker02   Ready    <none>   2d21h   v1.21.10   huanai

4.3 多维度标签

4.3.1 设置多维度标签

也可以加其它的多维度标签,用于不同的需要区分的场景

如把k8s-master03标签为华南区,A机房,测试环境,游戏业务

[root@k8s-master01 ~]# kubectl label node k8s-master03 zone=A env=test bussiness=game
node/k8s-master03 labeled
[root@k8s-master01 ~]# kubectl get nodes k8s-master03 --show-labels
NAME          STATUS   ROLES    AGE     VERSION    LABELS
k8s-master03   Ready    <none>   2d21h   v1.21.10   beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,bussiness=game,env=test,kubernetes.io/arch=amd64,kubernetes.io/hostname=k8s-master03,kubernetes.io/os=linux,zone=A

4.3.2 显示节点的相应标签

[root@k8s-master01 ~]# kubectl get nodes -L region,zone
NAME          STATUS   ROLES    AGE     VERSION    REGION   ZONE
k8s-master01   Ready    <none>   2d21h   v1.21.10
k8s-master02   Ready    <none>   2d21h   v1.21.10
k8s-master03   Ready    <none>   2d21h   v1.21.10            A
k8s-worker02   Ready    <none>   2d21h   v1.21.10   huanai

4.3.3 查找region=huanai的节点

[root@k8s-master01 ~]# kubectl get nodes -l region=huanai
NAME          STATUS   ROLES    AGE     VERSION
k8s-worker02  Ready    <none>   2d21h   v1.21.10

4.3.4 标签的修改

[root@k8s-master01 ~]# kubectl label node k8s-master03 bussiness=ad --overwrite=true
node/k8s-master03 labeled
加上--overwrite=true覆盖原标签的value进行修改操作
[root@k8s-master01 ~]# kubectl get nodes -L bussiness
NAME          STATUS   ROLES    AGE     VERSION    BUSSINESS
k8s-master01   Ready    <none>   2d21h   v1.21.10
k8s-master02   Ready    <none>   2d21h   v1.21.10
k8s-master03   Ready    <none>   2d21h   v1.21.10   ad
k8s-worker02   Ready    <none>   2d21h   v1.21.10

4.3.5 标签的删除

使用key加一个减号的写法来取消标签

[root@k8s-master02 ~]# kubectl label node k8s-worker02 region-
node/k8s-worker02 labeled

4.3.6 标签选择器

标签选择器主要有2类:

  • 等值关系: =, !=
  • 集合关系: KEY in {VALUE1, VALUE2…}
[root@k8s-master01 ~]# kubectl label node k8s-master02 env=test1
node/k8s-master02 labeled
[root@k8s-master01 ~]# kubectl label node k8s-master03 env=test2
node/k8s-master03 labeled
[root@k8s-master01 ~]# kubectl get node -l "env in(test1,test2)"
NAME          STATUS   ROLES    AGE     VERSION
k8s-master02   Ready    <none>   2d21h   v1.21.10
k8s-master03   Ready    <none>   2d21h   v1.21.10