主节点缺少节点角色 - 在 Kubespray 的帮助下完成 Kubernetes 安装
Node role is missing for Master node - Kubernetes installation done with the help of Kubespray
全新安装具有 3 个节点的 Kubernetes 集群后（2 个主节点和 3 个节点）
即，Masters 也被分配为 worker 节点。
安装成功后，我得到了节点的以下角色。如图所示，主节点缺少节点角色。
$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
node1 Ready master 12d v1.18.5
node2 Ready master 12d v1.18.5
node3 Ready <none> 12d v1.18.5
inventory/mycluster/hosts.yaml
all:
hosts:
node1:
ansible_host: 10.1.10.110
ip: 10.1.10.110
access_ip: 10.1.10.110
node2:
ansible_host: 10.1.10.111
ip: 10.1.10.111
access_ip: 10.1.10.111
node3:
ansible_host: 10.1.10.112
ip: 10.1.10.112
access_ip: 10.1.10.112
children:
kube-master:
hosts:
node1:
node2:
kube-node:
hosts:
node1:
node2:
node3:
etcd:
hosts:
node1:
node2:
node3:
k8s-cluster:
children:
kube-master:
kube-node:
calico-rr:
hosts: {}
vault:
hosts:
node1
node2
node3
网络插件：Flannel
用于调用ansible的命令：
ansible-playbook -i inventory/mycluster/hosts.yaml --become cluster.yml
如何让主节点兼作工作节点？
Kubectl 描述 node1 输出：
kubectl describe node node1
Name: node1
Roles: master
Labels: beta.kubernetes.io/arch=amd64
beta.kubernetes.io/os=linux
kubernetes.io/arch=amd64
kubernetes.io/hostname=node1
kubernetes.io/os=linux
node-role.kubernetes.io/master=
Annotations: flannel.alpha.coreos.com/backend-data: {"VtepMAC":"a6:bb:9e:2a:7e:a8"}
flannel.alpha.coreos.com/backend-type: vxlan
flannel.alpha.coreos.com/kube-subnet-manager: true
flannel.alpha.coreos.com/public-ip: 10.1.10.110
kubeadm.alpha.kubernetes.io/cri-socket: /var/run/dockershim.sock
node.alpha.kubernetes.io/ttl: 0
volumes.kubernetes.io/controller-managed-attach-detach: true
CreationTimestamp: Wed, 01 Jul 2020 09:26:15 -0700
Taints: <none>
Unschedulable: false
Lease:
HolderIdentity: node1
AcquireTime: <unset>
RenewTime: Tue, 14 Jul 2020 06:39:58 -0700
Conditions:
Type Status LastHeartbeatTime LastTransitionTime Reason Message
---- ------ ----------------- ------------------ ------ -------
NetworkUnavailable False Fri, 10 Jul 2020 12:51:05 -0700 Fri, 10 Jul 2020 12:51:05 -0700 FlannelIsUp Flannel is running on this node
MemoryPressure False Tue, 14 Jul 2020 06:40:02 -0700 Fri, 03 Jul 2020 15:00:26 -0700 KubeletHasSufficientMemory kubelet has sufficient memory available
DiskPressure False Tue, 14 Jul 2020 06:40:02 -0700 Fri, 03 Jul 2020 15:00:26 -0700 KubeletHasNoDiskPressure kubelet has no disk pressure
PIDPressure False Tue, 14 Jul 2020 06:40:02 -0700 Fri, 03 Jul 2020 15:00:26 -0700 KubeletHasSufficientPID kubelet has sufficient PID available
Ready True Tue, 14 Jul 2020 06:40:02 -0700 Mon, 06 Jul 2020 10:45:01 -0700 KubeletReady kubelet is posting ready status
Addresses:
InternalIP: 10.1.10.110
Hostname: node1
Capacity:
cpu: 8
ephemeral-storage: 51175Mi
hugepages-1Gi: 0
hugepages-2Mi: 0
memory: 32599596Ki
pods: 110
Allocatable:
cpu: 7800m
ephemeral-storage: 48294789041
hugepages-1Gi: 0
hugepages-2Mi: 0
memory: 31997196Ki
pods: 110
System Info:
Machine ID: c8690497b9704d2d975c33155c9fa69e
System UUID: 00000000-0000-0000-0000-AC1F6B96768A
Boot ID: 5e3eabe0-7732-4e6d-b25d-7eeec347d6c6
Kernel Version: 3.10.0-1127.13.1.el7.x86_64
OS Image: CentOS Linux 7 (Core)
Operating System: linux
Architecture: amd64
Container Runtime Version: docker://19.3.12
Kubelet Version: v1.18.5
Kube-Proxy Version: v1.18.5
PodCIDR: 10.233.64.0/24
PodCIDRs: 10.233.64.0/24
Non-terminated Pods: (9 in total)
Namespace Name CPU Requests CPU Limits Memory Requests Memory Limits AGE
--------- ---- ------------ ---------- --------------- ------------- ---
default httpd-deployment-598596ddfc-n56jq 0 (0%) 0 (0%) 0 (0%) 0 (0%) 7d20h
kube-system coredns-dff8fc7d-lb6bh 100m (1%) 0 (0%) 70Mi (0%) 170Mi (0%) 3d17h
kube-system kube-apiserver-node1 250m (3%) 0 (0%) 0 (0%) 0 (0%) 12d
kube-system kube-controller-manager-node1 200m (2%) 0 (0%) 0 (0%) 0 (0%) 12d
kube-system kube-flannel-px8cj 150m (1%) 300m (3%) 64M (0%) 500M (1%) 3d17h
kube-system kube-proxy-6spl2 0 (0%) 0 (0%) 0 (0%) 0 (0%) 3d17h
kube-system kube-scheduler-node1 100m (1%) 0 (0%) 0 (0%) 0 (0%) 12d
kube-system kubernetes-metrics-scraper-54fbb4d595-28vvc 0 (0%) 0 (0%) 0 (0%) 0 (0%) 7d20h
kube-system nodelocaldns-rxs4f 100m (1%) 0 (0%) 70Mi (0%) 170Mi (0%) 12d
Allocated resources:
(Total limits may be over 100 percent, i.e., overcommitted.)
Resource Requests Limits
-------- -------- ------
cpu 900m (11%) 300m (3%)
memory 205860Ki (0%) 856515840 (2%)
ephemeral-storage 0 (0%) 0 (0%)
hugepages-1Gi 0 (0%) 0 (0%)
hugepages-2Mi 0 (0%) 0 (0%)
Events: <none>
How can I make master node to be work as worker node as well ?
使用以下命令从主节点移除 NoSchedule 污点
kubectl taint node node1 node-role.kubernetes.io/master:NoSchedule-
kubectl taint node node2 node-role.kubernetes.io/master:NoSchedule-
此后 node1 和 node2 将变得像工作节点，并且 pods 可以在它们上安排。
全新安装具有 3 个节点的 Kubernetes 集群后（2 个主节点和 3 个节点） 即，Masters 也被分配为 worker 节点。
安装成功后，我得到了节点的以下角色。如图所示，主节点缺少节点角色。
$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
node1 Ready master 12d v1.18.5
node2 Ready master 12d v1.18.5
node3 Ready <none> 12d v1.18.5
inventory/mycluster/hosts.yaml
all:
hosts:
node1:
ansible_host: 10.1.10.110
ip: 10.1.10.110
access_ip: 10.1.10.110
node2:
ansible_host: 10.1.10.111
ip: 10.1.10.111
access_ip: 10.1.10.111
node3:
ansible_host: 10.1.10.112
ip: 10.1.10.112
access_ip: 10.1.10.112
children:
kube-master:
hosts:
node1:
node2:
kube-node:
hosts:
node1:
node2:
node3:
etcd:
hosts:
node1:
node2:
node3:
k8s-cluster:
children:
kube-master:
kube-node:
calico-rr:
hosts: {}
vault:
hosts:
node1
node2
node3
网络插件：Flannel
用于调用ansible的命令：
ansible-playbook -i inventory/mycluster/hosts.yaml --become cluster.yml
如何让主节点兼作工作节点？
Kubectl 描述 node1 输出：
kubectl describe node node1
Name: node1
Roles: master
Labels: beta.kubernetes.io/arch=amd64
beta.kubernetes.io/os=linux
kubernetes.io/arch=amd64
kubernetes.io/hostname=node1
kubernetes.io/os=linux
node-role.kubernetes.io/master=
Annotations: flannel.alpha.coreos.com/backend-data: {"VtepMAC":"a6:bb:9e:2a:7e:a8"}
flannel.alpha.coreos.com/backend-type: vxlan
flannel.alpha.coreos.com/kube-subnet-manager: true
flannel.alpha.coreos.com/public-ip: 10.1.10.110
kubeadm.alpha.kubernetes.io/cri-socket: /var/run/dockershim.sock
node.alpha.kubernetes.io/ttl: 0
volumes.kubernetes.io/controller-managed-attach-detach: true
CreationTimestamp: Wed, 01 Jul 2020 09:26:15 -0700
Taints: <none>
Unschedulable: false
Lease:
HolderIdentity: node1
AcquireTime: <unset>
RenewTime: Tue, 14 Jul 2020 06:39:58 -0700
Conditions:
Type Status LastHeartbeatTime LastTransitionTime Reason Message
---- ------ ----------------- ------------------ ------ -------
NetworkUnavailable False Fri, 10 Jul 2020 12:51:05 -0700 Fri, 10 Jul 2020 12:51:05 -0700 FlannelIsUp Flannel is running on this node
MemoryPressure False Tue, 14 Jul 2020 06:40:02 -0700 Fri, 03 Jul 2020 15:00:26 -0700 KubeletHasSufficientMemory kubelet has sufficient memory available
DiskPressure False Tue, 14 Jul 2020 06:40:02 -0700 Fri, 03 Jul 2020 15:00:26 -0700 KubeletHasNoDiskPressure kubelet has no disk pressure
PIDPressure False Tue, 14 Jul 2020 06:40:02 -0700 Fri, 03 Jul 2020 15:00:26 -0700 KubeletHasSufficientPID kubelet has sufficient PID available
Ready True Tue, 14 Jul 2020 06:40:02 -0700 Mon, 06 Jul 2020 10:45:01 -0700 KubeletReady kubelet is posting ready status
Addresses:
InternalIP: 10.1.10.110
Hostname: node1
Capacity:
cpu: 8
ephemeral-storage: 51175Mi
hugepages-1Gi: 0
hugepages-2Mi: 0
memory: 32599596Ki
pods: 110
Allocatable:
cpu: 7800m
ephemeral-storage: 48294789041
hugepages-1Gi: 0
hugepages-2Mi: 0
memory: 31997196Ki
pods: 110
System Info:
Machine ID: c8690497b9704d2d975c33155c9fa69e
System UUID: 00000000-0000-0000-0000-AC1F6B96768A
Boot ID: 5e3eabe0-7732-4e6d-b25d-7eeec347d6c6
Kernel Version: 3.10.0-1127.13.1.el7.x86_64
OS Image: CentOS Linux 7 (Core)
Operating System: linux
Architecture: amd64
Container Runtime Version: docker://19.3.12
Kubelet Version: v1.18.5
Kube-Proxy Version: v1.18.5
PodCIDR: 10.233.64.0/24
PodCIDRs: 10.233.64.0/24
Non-terminated Pods: (9 in total)
Namespace Name CPU Requests CPU Limits Memory Requests Memory Limits AGE
--------- ---- ------------ ---------- --------------- ------------- ---
default httpd-deployment-598596ddfc-n56jq 0 (0%) 0 (0%) 0 (0%) 0 (0%) 7d20h
kube-system coredns-dff8fc7d-lb6bh 100m (1%) 0 (0%) 70Mi (0%) 170Mi (0%) 3d17h
kube-system kube-apiserver-node1 250m (3%) 0 (0%) 0 (0%) 0 (0%) 12d
kube-system kube-controller-manager-node1 200m (2%) 0 (0%) 0 (0%) 0 (0%) 12d
kube-system kube-flannel-px8cj 150m (1%) 300m (3%) 64M (0%) 500M (1%) 3d17h
kube-system kube-proxy-6spl2 0 (0%) 0 (0%) 0 (0%) 0 (0%) 3d17h
kube-system kube-scheduler-node1 100m (1%) 0 (0%) 0 (0%) 0 (0%) 12d
kube-system kubernetes-metrics-scraper-54fbb4d595-28vvc 0 (0%) 0 (0%) 0 (0%) 0 (0%) 7d20h
kube-system nodelocaldns-rxs4f 100m (1%) 0 (0%) 70Mi (0%) 170Mi (0%) 12d
Allocated resources:
(Total limits may be over 100 percent, i.e., overcommitted.)
Resource Requests Limits
-------- -------- ------
cpu 900m (11%) 300m (3%)
memory 205860Ki (0%) 856515840 (2%)
ephemeral-storage 0 (0%) 0 (0%)
hugepages-1Gi 0 (0%) 0 (0%)
hugepages-2Mi 0 (0%) 0 (0%)
Events: <none>
How can I make master node to be work as worker node as well ?
使用以下命令从主节点移除 NoSchedule 污点
kubectl taint node node1 node-role.kubernetes.io/master:NoSchedule-
kubectl taint node node2 node-role.kubernetes.io/master:NoSchedule-
此后 node1 和 node2 将变得像工作节点，并且 pods 可以在它们上安排。