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/-default.conf
{
        "name": "flannel",
        "type": "flannel",
        "delegate": {
            "bridge": "docker0",
            "isDefaultGateway": true,
            "mtu":
        }
}
[root@linux-node3 ~]# mkdir -p /etc/cni/net.d
[root@linux-node2 ~]# scp /etc/cni/net.d/-default.conf 192.168.56.130:/etc/cni/net.d/-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= \
  --logtostderr=false \
  --log-dir=/opt/kubernetes/log
Restart=on-failure
RestartSec=
 
[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= \
  --logtostderr=false \
  --log-dir=/opt/kubernetes/log
Restart=on-failure
RestartSec=

（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 -- :: CST; 16h ago
     Docs: https://github.com/GoogleCloudPlatform/kubernetes
 Main PID:  (kubelet)
   CGroup: /system.slice/kubelet.service
           └─ /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  :: linux-node2.example.com kubelet[]: E0601 ::09.355765    summary.go:] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月  :: linux-node2.example.com kubelet[]: E0601 ::19.363906    summary.go:] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月  :: linux-node2.example.com kubelet[]: E0601 ::29.385439    summary.go:] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月  :: linux-node2.example.com kubelet[]: E0601 ::39.393790    summary.go:] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月  :: linux-node2.example.com kubelet[]: E0601 ::49.401081    summary.go:] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月  :: linux-node2.example.com kubelet[]: E0601 ::59.407863    summary.go:] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月  :: linux-node2.example.com kubelet[]: E0601 ::09.415552    summary.go:] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月  :: linux-node2.example.com kubelet[]: E0601 ::19.425998    summary.go:] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月  :: linux-node2.example.com kubelet[]: E0601 ::29.443804    summary.go:] Failed to get system container stats for "/system.slice/kubelet.service": failed to...
6月  :: linux-node2.example.com kubelet[]: E0601 ::39.450814    summary.go:] 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":
  },
  "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= \
  --logtostderr=false \
  --log-dir=/opt/kubernetes/log
 
Restart=on-failure
RestartSec=
LimitNOFILE=
 
[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                                         %     .4KB/s   :
[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                                         %      .9KB/s   :

（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. (size=)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  10.1.0.1: rr persistent
  -> 192.168.56.110:          Masq                             
 
[root@linux-node3 ~]# ipvsadm -Ln
IP Virtual Server version 1.2. (size=)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  10.1.0.1: rr persistent
  -> 192.168.56.110:          Masq                             
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 -- :: EDT; 1s ago
     Docs: https://github.com/GoogleCloudPlatform/kubernetes
  Process:  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= --logtostderr=false --log-dir=/opt/kubernetes/log (code=exited, status=)
 Main PID:  (code=exited, status=)
 
May  :: linux-node3.example.com systemd[]: Unit kubelet.service entered failed state.
May  :: linux-node3.example.com systemd[]: kubelet.service failed.
[root@linux-node3 ~]# tailf /var/log/messages
......
May  :: linux-node3 kubelet: F0530 ::24.134612    server.go:] 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=
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=
LimitNPROC=
LimitCORE=infinity
TimeoutStartSec=
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

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今天在阿里云的linux上搭建ftp服务的时候,搭建成功之后,上传文件时总提示553 Could not create file,找了半天原因,终于解决了 ftp主目录为/home/myftp /ho ...
el表达式便利map集合
<c:forEach items="${b.goodMap}" var="entry" varStatus="status"> ...
November 14th 2016 Week 47th Monday
There are far, far better things ahead than any we leave behind. 前方,有更美好的未来. Can I see those better ...
Git忽略提交 .gitignore配置。自动生成IDE的.gitignore。解决gitignore不生效
语法以”#”号开头表示注释: 以斜杠“/”开头表示目录: 以星号“*”通配多个字符: 以问号“?”通配单个字符以方括号“[]”包含单个字符的匹配列表: 以叹号“!”表示不忽略(跟踪)匹配到的文件或 ...
索引&切片切割split
索引 s[n] # 中括号里n为一个数字切片 s[0:9] ...
1031. [JSOI2007]字符加密【后缀数组】
Description 喜欢钻研问题的JS同学,最近又迷上了对加密方法的思考.一天,他突然想出了一种他认为是终极的加密办法 :把需要加密的信息排成一圈,显然,它们有很多种不同的读法.例如下图,可以读作 ...
1060. [ZJOI2007]时态同步【树形DP】
Description 小Q在电子工艺实习课上学习焊接电路板.一块电路板由若干个元件组成,我们不妨称之为节点,并将其用数字1,2,3….进行标号.电路板的各个节点由若干不相交的导线相连接,且对于电路 ...