kubeadm配備kubernetes 1.11.0の問題記録

システム環境

[root@kubeadm ~]# cat /etc/redhat-release 
CentOS Linux release 7.5.1804 (Core) 

selinuxを閉じる

[root@kubeadm ~]# cat /etc/selinux/config 

# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
#     enforcing - SELinux security policy is enforced.
#     permissive - SELinux prints warnings instead of enforcing.
#     disabled - No SELinux policy is loaded.
SELINUX=disabled
# SELINUXTYPE= can take one of three two values:
#     targeted - Targeted processes are protected,
#     minimum - Modification of targeted policy. Only selected processes are protected. 
#     mls - Multi Level Security protection.
SELINUXTYPE=targeted 

dockerのcgroup-driverドライバと同じようにkubeletの起動環境変数を編集します.
dockerのcgroup-driver駆動

[root@kubeadm ~]# docker info
Containers: 10
 Running: 10
 Paused: 0
 Stopped: 0
Images: 7
Server Version: 1.13.1
Storage Driver: overlay2
 Backing Filesystem: xfs
 Supports d_type: true
 Native Overlay Diff: false
Logging Driver: journald
Cgroup Driver: systemd

kubeletのcgroup-driver駆動

[root@kubeadm ~]# cat /etc/default/kubelet 
KUBELET_KUBEADM_EXTRA_ARGS=--cgroup-driver=systemd

dockerのインストール

yum install -y docker
systemctl enable docker && systemctl start docker

Googleのyumソースを追加

[root@kubeadm ~]# cat /etc/yum.repos.d/kubernetes.repo 
[kubernetes]
name=Kubernetes
baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg

取付kubelet kubeadm kubectl

yum install -y kubelet kubeadm kubectl
systemctl enable kubelet

注意:このステップはsystemctl start kubeletを直接実行することはできません.No側はエラーを報告し、kubeletも起動に成功しません.

7  29 12:17:19 kubeadm systemd[1]: Started kubelet: The Kubernetes Node Agent.
7  29 12:17:19 kubeadm systemd[1]: Starting kubelet: The Kubernetes Node Agent...
7  29 12:17:20 kubeadm kubelet[32751]: F0729 12:17:20.026220   32751 server.go:190] failed to load Kubelet config file /var/lib/kubelet/config.yaml, error failed to read kubelet config file "/var/lib/kubelet/config.yaml", error: open /var/lib/kubelet/config.yaml: no such file or directory

関連記事
直接実行

[root@kubeadm ~]# kubeadm init
[init] using Kubernetes version: v1.11.1
[preflight] running pre-flight checks
    [WARNING Firewalld]: firewalld is active, please ensure ports [6443 10250] are open or your cluster may not function correctly
I0729 12:24:37.097036     574 kernel_validator.go:81] Validating kernel version
I0729 12:24:37.097124     574 kernel_validator.go:96] Validating kernel config
    [WARNING Hostname]: hostname "kubeadm" could not be reached
    [WARNING Hostname]: hostname "kubeadm" lookup kubeadm on 10.155.0.1:53: no such host
[preflight/images] Pulling images required for setting up a Kubernetes cluster
[preflight/images] This might take a minute or two, depending on the speed of your internet connection
[preflight/images] You can also perform this action in beforehand using 'kubeadm config images pull'

[kubelet] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[preflight] Activating the kubelet service
[certificates] Generated ca certificate and key.
[certificates] Generated apiserver certificate and key.

[root@kubeadm ~]# systemctl status kubelet
● kubelet.service - kubelet: The Kubernetes Node Agent
   Loaded: loaded (/etc/systemd/system/kubelet.service; enabled; vendor preset: disabled)
  Drop-In: /etc/systemd/system/kubelet.service.d
           └─10-kubeadm.conf
   Active: active (running) since   2018-07-29 12:27:18 CST; 1min 10s ago
     Docs: http://kubernetes.io/docs/
 Main PID: 917 (kubelet)
   CGroup: /system.slice/kubelet.service
           └─917 /usr/bin/kubelet --bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf --kubeconfig=/etc/kubernetes/kubelet.conf --config=/var/lib...

7  29 12:28:10 kubeadm kubelet[917]: W0729 12:28:10.689546     917 cni.go:172] Unable to update cni config: No networks found in /etc/cni/net.d
7  29 12:28:10 kubeadm kubelet[917]: E0729 12:28:10.689653     917 kubelet.go:2110] Container runtime network not ready: NetworkReady=false reas...itialized
7  29 12:28:15 kubeadm kubelet[917]: W0729 12:28:15.691030     917 cni.go:172] Unable to update cni config: No networks found in /etc/cni/net.d
7  29 12:28:15 kubeadm kubelet[917]: E0729 12:28:15.691284     917 kubelet.go:2110] Container runtime network not ready: NetworkReady=false reas...itialized
7  29 12:28:20 kubeadm kubelet[917]: E0729 12:28:20.683083     917 summary.go:102] Failed to get system container stats for "/system.slice/kubelet.servic...
7  29 12:28:20 kubeadm kubelet[917]: E0729 12:28:20.683103     917 summary.go:102] Failed to get system container stats for "/system.slice/docke....service"
7  29 12:28:20 kubeadm kubelet[917]: W0729 12:28:20.692520     917 cni.go:172] Unable to update cni config: No networks found in /etc/cni/net.d
7  29 12:28:20 kubeadm kubelet[917]: E0729 12:28:20.692688     917 kubelet.go:2110] Container runtime network not ready: NetworkReady=false reas...itialized
7  29 12:28:25 kubeadm kubelet[917]: W0729 12:28:25.694158     917 cni.go:172] Unable to update cni config: No networks found in /etc/cni/net.d
7  29 12:28:25 kubeadm kubelet[917]: E0729 12:28:25.694261     917 kubelet.go:2110] Container runtime network not ready: NetworkReady=false reas...itialized
Hint: Some lines were ellipsized, use -l to show in full.

以降は、以降の導入と低バージョンの導入と同じですが、ここでは詳しくは説明しません.
参考install-kubeadm