Kubernetes学习之路（四）之Node节点二进制部署

K8S Node节点部署

• 1、部署kubelet

（1）二进制包准备

[root@linux-node1 ~]# cd /usr/local/src/kubernetes/server/bin/
[root@linux-node1 bin]# cp kubelet kube-proxy /opt/kubernetes/bin/
[root@linux-node1 bin]# scp kubelet kube-proxy 192.168.56.120:/opt/kubernetes/bin/
[root@linux-node1 bin]# scp kubelet kube-proxy 192.168.56.130:/opt/kubernetes/bin/

（2）创建角色绑定

kubelet启动时会向kube-apiserver发送tsl bootstrap请求，所以需要将bootstrap的token设置成对应的角色，这样kubectl才有权限创建该请求。

[root@linux-node1 ~]# kubectl create clusterrolebinding kubelet-bootstrap --clusterrole=system:node-bootstrapper --user=kubelet-bootstrap
clusterrolebinding "kubelet-bootstrap" created

（3）创建 kubelet bootstrapping kubeconfig 文件 设置集群参数

[root@linux-node1 ~]# cd /usr/local/src/ssl
[root@linux-node1 ssl]# kubectl config set-cluster kubernetes 
   --certificate-authority=/opt/kubernetes/ssl/ca.pem 
   --embed-certs=true 
   --server=https://192.168.56.110:6443 
   --kubeconfig=bootstrap.kubeconfig
Cluster "kubernetes" set.

（4）设置客户端认证参数

[root@linux-node1 ssl]# kubectl config set-credentials kubelet-bootstrap 
   --token=ad6d5bb607a186796d8861557df0d17f 
   --kubeconfig=bootstrap.kubeconfig   
User "kubelet-bootstrap" set.

（5）设置上下文参数

[root@linux-node1 ssl]# kubectl config set-context default 
   --cluster=kubernetes 
   --user=kubelet-bootstrap 
   --kubeconfig=bootstrap.kubeconfig
Context "default" created.

（6）选择默认上下文

[root@linux-node1 ssl]# kubectl config use-context default --kubeconfig=bootstrap.kubeconfig
Switched to context "default".
[root@linux-node1 ssl]# cp bootstrap.kubeconfig /opt/kubernetes/cfg
[root@linux-node1 ssl]# scp bootstrap.kubeconfig 192.168.56.120:/opt/kubernetes/cfg
[root@linux-node1 ssl]# scp bootstrap.kubeconfig 192.168.56.130:/opt/kubernetes/cfg

• 2、部署kubelet 1.设置CNI支持

（1）配置CNI

[root@linux-node2 ~]# mkdir -p /etc/cni/net.d
[root@linux-node2 ~]# vim /etc/cni/net.d/10-default.conf
{
        "name": "flannel",
        "type": "flannel",
        "delegate": {
            "bridge": "docker0",
            "isDefaultGateway": true,
            "mtu": 1400
        }
}
[root@linux-node3 ~]# mkdir -p /etc/cni/net.d
[root@linux-node2 ~]# scp /etc/cni/net.d/10-default.conf 192.168.56.130:/etc/cni/net.d/10-default.conf

（2）创建kubelet数据存储目录

[root@linux-node2 ~]# mkdir /var/lib/kubelet
[root@linux-node3 ~]# mkdir /var/lib/kubelet

（3）创建kubelet服务配置

[root@linux-node2 ~]# vim /usr/lib/systemd/system/kubelet.service
[Unit]
Description=Kubernetes Kubelet
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
After=docker.service
Requires=docker.service

[Service]
WorkingDirectory=/var/lib/kubelet
ExecStart=/opt/kubernetes/bin/kubelet 
  --address=192.168.56.120 
  --hostname-override=192.168.56.120 
  --pod-infra-container-image=mirrorgooglecontainers/pause-amd64:3.0 
  --experimental-bootstrap-kubeconfig=/opt/kubernetes/cfg/bootstrap.kubeconfig 
  --kubeconfig=/opt/kubernetes/cfg/kubelet.kubeconfig 
  --cert-dir=/opt/kubernetes/ssl 
  --network-plugin=cni 
  --cni-conf-dir=/etc/cni/net.d 
  --cni-bin-dir=/opt/kubernetes/bin/cni 
  --cluster-dns=10.1.0.2 
  --cluster-domain=cluster.local. 
  --hairpin-mode hairpin-veth 
  --allow-privileged=true 
  --fail-swap-on=false 
  --logtostderr=true 
  --v=2 
  --logtostderr=false 
  --log-dir=/opt/kubernetes/log
Restart=on-failure
RestartSec=5



[root@linux-node3 ~]# vim /usr/lib/systemd/system/kubelet.service
[Unit]
Description=Kubernetes Kubelet
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
After=docker.service
Requires=docker.service

[Service]
WorkingDirectory=/var/lib/kubelet
ExecStart=/opt/kubernetes/bin/kubelet 
  --address=192.168.56.130 
  --hostname-override=192.168.56.130 
  --pod-infra-container-image=mirrorgooglecontainers/pause-amd64:3.0 
  --experimental-bootstrap-kubeconfig=/opt/kubernetes/cfg/bootstrap.kubeconfig 
  --kubeconfig=/opt/kubernetes/cfg/kubelet.kubeconfig 
  --cert-dir=/opt/kubernetes/ssl 
  --network-plugin=cni 
  --cni-conf-dir=/etc/cni/net.d 
  --cni-bin-dir=/opt/kubernetes/bin/cni 
  --cluster-dns=10.1.0.2 
  --cluster-domain=cluster.local. 
  --hairpin-mode hairpin-veth 
  --allow-privileged=true 
  --fail-swap-on=false 
  --logtostderr=true 
  --v=2 
  --logtostderr=false 
  --log-dir=/opt/kubernetes/log
Restart=on-failure
RestartSec=5

（4）启动Kubelet

[root@linux-node2 ~]# systemctl daemon-reload
[root@linux-node2 ~]# systemctl enable kubelet
[root@linux-node2 ~]# systemctl start kubelet
[root@linux-node2 kubernetes]# systemctl status kubelet

[root@linux-node3 ~]# systemctl daemon-reload
[root@linux-node3 ~]# systemctl enable kubelet
[root@linux-node3 ~]# systemctl start kubelet
[root@linux-node3 kubernetes]# systemctl status kubelet

在查看kubelet的状态，发现有如下报错Failed to get system container stats for "/system.slice/kubelet.service": failed to...此时需要调整kubelet的启动参数。

解决方法： 
在/usr/lib/systemd/system/kubelet.service的[service]新增: Environment="KUBELET_MY_ARGS=--runtime-cgroups=/systemd/system.slice --kubelet-cgroups=/systemd/system.slice" 
修改ExecStart: 在末尾新增$KUBELET_MY_ARGS

[root@linux-node2 system]# systemctl status kubelet
● kubelet.service - Kubernetes Kubelet
   Loaded: loaded (/usr/lib/systemd/system/kubelet.service; static; vendor preset: disabled)
   Active: active (running) since 四 2018-05-31 16:33:17 CST; 16h ago
     Docs: https://github.com/GoogleCloudPlatform/kubernetes
 Main PID: 53223 (kubelet)
   CGroup: /system.slice/kubelet.service
           └─53223 /opt/kubernetes/bin/kubelet --address=192.168.56.120 --hostname-override=192.168.56.120 --pod-infra-container-image=mirrorgooglecontainers/pause-amd64:3.0 --experiment...

6月 01 08:51:09 linux-node2.example.com kubelet[53223]: E0601 08:51:09.355765   53223 summary.go:102] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月 01 08:51:19 linux-node2.example.com kubelet[53223]: E0601 08:51:19.363906   53223 summary.go:102] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月 01 08:51:29 linux-node2.example.com kubelet[53223]: E0601 08:51:29.385439   53223 summary.go:102] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月 01 08:51:39 linux-node2.example.com kubelet[53223]: E0601 08:51:39.393790   53223 summary.go:102] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月 01 08:51:49 linux-node2.example.com kubelet[53223]: E0601 08:51:49.401081   53223 summary.go:102] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月 01 08:51:59 linux-node2.example.com kubelet[53223]: E0601 08:51:59.407863   53223 summary.go:102] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月 01 08:52:09 linux-node2.example.com kubelet[53223]: E0601 08:52:09.415552   53223 summary.go:102] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月 01 08:52:19 linux-node2.example.com kubelet[53223]: E0601 08:52:19.425998   53223 summary.go:102] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月 01 08:52:29 linux-node2.example.com kubelet[53223]: E0601 08:52:29.443804   53223 summary.go:102] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月 01 08:52:39 linux-node2.example.com kubelet[53223]: E0601 08:52:39.450814   53223 summary.go:102] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
Hint: Some lines were ellipsized, use -l to show in full.

（5）查看csr请求 注意是在linux-node1上执行。

[root@linux-node1 ssl]# kubectl get csr
NAME                                                   AGE       REQUESTOR           CONDITION
node-csr-6Wc7kmqBIaPOw83l2F1uCKN-uUaxfkVhIU8K93S5y1U   1m        kubelet-bootstrap   Pending
node-csr-fIXcxO7jyR1Au7nrpUXht19eXHnX1HdFl99-oq2sRsA   1m        kubelet-bootstrap   Pending

（6）批准kubelet 的 TLS 证书请求

[root@linux-node1 ssl]#  kubectl get csr|grep 'Pending' | awk 'NR>0{print $1}'| xargs kubectl certificate approve
certificatesigningrequest.certificates.k8s.io "node-csr-6Wc7kmqBIaPOw83l2F1uCKN-uUaxfkVhIU8K93S5y1U" approved
certificatesigningrequest.certificates.k8s.io "node-csr-fIXcxO7jyR1Au7nrpUXht19eXHnX1HdFl99-oq2sRsA" approved

[root@linux-node1 ssl]# kubectl get csr
NAME                                                   AGE       REQUESTOR           CONDITION
node-csr-6Wc7kmqBIaPOw83l2F1uCKN-uUaxfkVhIU8K93S5y1U   2m        kubelet-bootstrap   Approved,Issued
node-csr-fIXcxO7jyR1Au7nrpUXht19eXHnX1HdFl99-oq2sRsA   2m        kubelet-bootstrap   Approved,Issued

执行完毕后，查看节点状态已经是Ready的状态了 
[root@linux-node1 ssl]# kubectl get node
NAME             STATUS    ROLES     AGE       VERSION
192.168.56.120   Ready     <none>    50m       v1.10.1
192.168.56.130   Ready     <none>    46m       v1.10.1

• 3、部署Kubernetes Proxy

（1）配置kube-proxy使用LVS

[root@linux-node2 ~]# yum install -y ipvsadm ipset conntrack
[root@linux-node3 ~]# yum install -y ipvsadm ipset conntrack

（2）创建 kube-proxy 证书请求

[root@linux-node1 ~]# cd /usr/local/src/ssl/
[root@linux-node1 ssl]# vim kube-proxy-csr.json
{
  "CN": "system:kube-proxy",
  "hosts": [],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "ST": "BeiJing",
      "L": "BeiJing",
      "O": "k8s",
      "OU": "System"
    }
  ]
}

（3）生成证书

[root@linux-node1~]# cfssl gencert -ca=/opt/kubernetes/ssl/ca.pem 
   -ca-key=/opt/kubernetes/ssl/ca-key.pem 
   -config=/opt/kubernetes/ssl/ca-config.json 
   -profile=kubernetes  kube-proxy-csr.json | cfssljson -bare kube-proxy

（4）分发证书到所有Node节点

[root@linux-node1 ssl]# cp kube-proxy*.pem /opt/kubernetes/ssl/
[root@linux-node1 ssl]# scp kube-proxy*.pem 192.168.56.120:/opt/kubernetes/ssl/
[root@linux-node1 ssl]# scp kube-proxy*.pem 192.168.56.120:/opt/kubernetes/ssl/

（5）创建kube-proxy配置文件

[root@linux-node1 ssl]# kubectl config set-cluster kubernetes 
   --certificate-authority=/opt/kubernetes/ssl/ca.pem 
   --embed-certs=true 
   --server=https://192.168.56.110:6443 
   --kubeconfig=kube-proxy.kubeconfig
Cluster "kubernetes" set.

[root@linux-node1 ssl]# kubectl config set-credentials kube-proxy 
   --client-certificate=/opt/kubernetes/ssl/kube-proxy.pem 
   --client-key=/opt/kubernetes/ssl/kube-proxy-key.pem 
   --embed-certs=true 
   --kubeconfig=kube-proxy.kubeconfig
User "kube-proxy" set.

[root@linux-node1 ssl]# kubectl config set-context default 
   --cluster=kubernetes 
   --user=kube-proxy 
   --kubeconfig=kube-proxy.kubeconfig
Context "default" created.

[root@linux-node1 ssl]# kubectl config use-context default --kubeconfig=kube-proxy.kubeconfig
Switched to context "default".

（6）分发kubeconfig配置文件

[root@linux-node1 ssl]# cp kube-proxy.kubeconfig /opt/kubernetes/cfg/
[root@linux-node1 ssl]# scp kube-proxy.kubeconfig 192.168.56.120:/opt/kubernetes/cfg/
[root@linux-node1 ssl]# scp kube-proxy.kubeconfig 192.168.56.130:/opt/kubernetes/cfg/

（7）创建kube-proxy服务配置

[root@linux-node1 ssl]# mkdir /var/lib/kube-proxy
[root@linux-node2 ssl]# mkdir /var/lib/kube-proxy
[root@linux-node3 ssl]# mkdir /var/lib/kube-proxy

[root@linux-node1 ~]# vim /usr/lib/systemd/system/kube-proxy.service
[Unit]
Description=Kubernetes Kube-Proxy Server
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
After=network.target

[Service]
WorkingDirectory=/var/lib/kube-proxy
ExecStart=/opt/kubernetes/bin/kube-proxy 
  --bind-address=192.168.56.120 
  --hostname-override=192.168.56.120 
  --kubeconfig=/opt/kubernetes/cfg/kube-proxy.kubeconfig 
--masquerade-all 
  --feature-gates=SupportIPVSProxyMode=true 
  --proxy-mode=ipvs 
  --ipvs-min-sync-period=5s 
  --ipvs-sync-period=5s 
  --ipvs-scheduler=rr 
  --logtostderr=true 
  --v=2 
  --logtostderr=false 
  --log-dir=/opt/kubernetes/log

Restart=on-failure
RestartSec=5
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target

[root@linux-node1 ssl]# scp /usr/lib/systemd/system/kube-proxy.service 192.168.56.120:/usr/lib/systemd/system/kube-proxy.service
kube-proxy.service                                         100%  701   109.4KB/s   00:00    
[root@linux-node1 ssl]# scp /usr/lib/systemd/system/kube-proxy.service 192.168.56.130:/usr/lib/systemd/system/kube-proxy.service
kube-proxy.service                                         100%  701    34.9KB/s   00:00    

（8）启动Kubernetes Proxy

[root@linux-node2 ~]# systemctl daemon-reload
[root@linux-node2 ~]# systemctl enable kube-proxy
[root@linux-node2 ~]# systemctl start kube-proxy
[root@linux-node2 ~]# systemctl status kube-proxy

[root@linux-node3 ~]# systemctl daemon-reload
[root@linux-node3 ~]# systemctl enable kube-proxy
[root@linux-node3 ~]# systemctl start kube-proxy
[root@linux-node3 ~]# systemctl status kube-proxy

检查LVS状态，可以看到已经创建了一个LVS集群，将来自10.1.0.1:443的请求转到192.168.56.110:6443，而6443就是api-server的端口
[root@linux-node2 ~]# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  10.1.0.1:443 rr persistent 10800
  -> 192.168.56.110:6443          Masq    1      0          0         

[root@linux-node3 ~]# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  10.1.0.1:443 rr persistent 10800
  -> 192.168.56.110:6443          Masq    1      0          0         

如果你在两台实验机器都安装了kubelet和proxy服务，使用下面的命令可以检查状态：

[root@linux-node1 ssl]#  kubectl get node
NAME            STATUS    ROLES     AGE       VERSION
192.168.56.120   Ready     <none>    22m       v1.10.1
192.168.56.130   Ready     <none>    3m        v1.10.1

到此，K8S的集群就部署完毕，由于K8S本身不支持网络，需要借助第三方网络才能进行创建Pod，将在下一节学习Flannel网络为K8S提供网络支持。

（9）遇到的问题：kubelet无法启动，kubectl get node 提示：no resource found

[root@linux-node1 ssl]#  kubectl get node
No resources found.

[root@linux-node3 ~]# systemctl status kubelet
● kubelet.service - Kubernetes Kubelet
   Loaded: loaded (/usr/lib/systemd/system/kubelet.service; static; vendor preset: disabled)
   Active: activating (auto-restart) (Result: exit-code) since Wed 2018-05-30 04:48:29 EDT; 1s ago
     Docs: https://github.com/GoogleCloudPlatform/kubernetes
  Process: 16995 ExecStart=/opt/kubernetes/bin/kubelet --address=192.168.56.130 --hostname-override=192.168.56.130 --pod-infra-container-image=mirrorgooglecontainers/pause-amd64:3.0 --experimental-bootstrap-kubeconfig=/opt/kubernetes/cfg/bootstrap.kubeconfig --kubeconfig=/opt/kubernetes/cfg/kubelet.kubeconfig --cert-dir=/opt/kubernetes/ssl --network-plugin=cni --cni-conf-dir=/etc/cni/net.d --cni-bin-dir=/opt/kubernetes/bin/cni --cluster-dns=10.1.0.2 --cluster-domain=cluster.local. --hairpin-mode hairpin-veth --allow-privileged=true --fail-swap-on=false --logtostderr=true --v=2 --logtostderr=false --log-dir=/opt/kubernetes/log (code=exited, status=255)
 Main PID: 16995 (code=exited, status=255)

May 30 04:48:29 linux-node3.example.com systemd[1]: Unit kubelet.service entered failed state.
May 30 04:48:29 linux-node3.example.com systemd[1]: kubelet.service failed.
[root@linux-node3 ~]# tailf /var/log/messages
......
May 30 04:46:24 linux-node3 kubelet: F0530 04:46:24.134612   16207 server.go:233] failed to run Kubelet: failed to create kubelet: misconfiguration: kubelet cgroup driver: "cgroupfs" is different from docker cgroup driver: "systemd"

提示kubelet使用的cgroup驱动类型和docker的cgroup驱动类型不一致。进行查看docker.service

[Unit]
Description=Docker Application Container Engine
Documentation=http://docs.docker.com
After=network.target
Wants=docker-storage-setup.service
Requires=docker-cleanup.timer

[Service]
Type=notify
NotifyAccess=all
KillMode=process
EnvironmentFile=-/etc/sysconfig/docker
EnvironmentFile=-/etc/sysconfig/docker-storage
EnvironmentFile=-/etc/sysconfig/docker-network
Environment=GOTRACEBACK=crash
Environment=DOCKER_HTTP_HOST_COMPAT=1
Environment=PATH=/usr/libexec/docker:/usr/bin:/usr/sbin
ExecStart=/usr/bin/dockerd-current 
          --add-runtime docker-runc=/usr/libexec/docker/docker-runc-current 
          --default-runtime=docker-runc 
          --exec-opt native.cgroupdriver=systemd    ###修改此处"systemd"为"cgroupfs"
          --userland-proxy-path=/usr/libexec/docker/docker-proxy-current 
          $OPTIONS 
          $DOCKER_STORAGE_OPTIONS 
          $DOCKER_NETWORK_OPTIONS 
          $ADD_REGISTRY 
          $BLOCK_REGISTRY 
          $INSECURE_REGISTRY
ExecReload=/bin/kill -s HUP $MAINPID
LimitNOFILE=1048576
LimitNPROC=1048576
LimitCORE=infinity
TimeoutStartSec=0
Restart=on-abnormal
MountFlags=slave

[Install]
WantedBy=multi-user.target
[root@linux-node3 ~]# systemctl daemon-reload
[root@linux-node3 ~]# systemctl restart docker.service
[root@linux-node3 ~]# systemctl restart kubelet