部署K8S单机环境

2021-01-31

字数统计: 2.5k字 | 阅读时长≈ 15分

1.部署基础环境

[root@leoheng-k8s ~]# vim sys_init.sh 
#!/bin/bash
yum install -y yum-utils git* vim lrzsz wget g++ gcc yum-utils device-mapper-persistent-data lvm2
systemctl stop firewalld
setenforce 0
yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
yum makecache fast
yum install -y docker-ce*
systemctl start docker
systemctl status docker
systemctl enable docker

2.部署K8S单机环境

1.配置Ipvs模块，用于kube-proxy。
[root@leoheng-k8s ~]# vim /etc/sysconfig/modules/ipvs.modules
modprobe -- ip_vs_rr
modprobe -- ip_vs_wrr
modprobe -- ip_vs_sh
modprobe -- nf_conntrack_ipv4
[root@leoheng-k8s ~]# chmod 755 /etc/sysconfig/modules/ipvs.modules && bash /etc/sysconfig/modules/ipvs.modules && lsmod | grep -e ip_vs -e nf_conntrack_ipv4
nf_conntrack_ipv4      15053  0 
nf_defrag_ipv4         12729  1 nf_conntrack_ipv4
ip_vs_sh               12688  0 
ip_vs_wrr              12697  0 
ip_vs_rr               12600  0 
ip_vs                 145458  6 ip_vs_rr,ip_vs_sh,ip_vs_wrr
nf_conntrack          139264  2 ip_vs,nf_conntrack_ipv4
libcrc32c              12644  2 ip_vs,nf_conntrack
[root@leoheng-k8s ~]#

2.配置K8s的仓库源（阿里云）

[root@leoheng-k8s ~]# cat /etc/yum.repos.d/k8s.repo 
[kubernetes]
name=Kubernetes
baseurl=http://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=0
repo_gpgcheck=0
gpgkey=http://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg
       http://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
[root@leoheng-k8s ~]#

3.安装kubeadm、kubelet、kubectl

[root@leoheng-k8s ~]# yum update
[root@leoheng-k8s ~]# yum makecache fast
[root@leoheng-k8s ~]# yum install -y kubelet kubeadm kubectl
[root@leoheng-k8s ~]# systemctl enable kubelet && systemctl start kubelet
Created symlink from /etc/systemd/system/multi-user.target.wants/kubelet.service to /usr/lib/systemd/system/kubelet.service.
[root@leoheng-k8s ~]# kubeadm config images list 
k8s.gcr.io/kube-apiserver:v1.20.2
k8s.gcr.io/kube-controller-manager:v1.20.2
k8s.gcr.io/kube-scheduler:v1.20.2
k8s.gcr.io/kube-proxy:v1.20.2
k8s.gcr.io/pause:3.2
k8s.gcr.io/etcd:3.4.13-0
k8s.gcr.io/coredns:1.7.0
[root@leoheng-k8s ~]#

4.执行脚本拉取国内镜像（阿里云）

[root@leoheng-k8s /]# vim k8s_imags.sh
#!/bin/bash
for i in `kubeadm config images list`; do 
imageName=${i#k8s.gcr.io/}
docker pull registry.aliyuncs.com/google_containers/$imageName
docker tag registry.aliyuncs.com/google_containers/$imageName k8s.gcr.io/$imageName
docker rmi registry.aliyuncs.com/google_containers/$imageName
done;
[root@leoheng-k8s /]# chmod +x k8s_imags.sh 
[root@leoheng-k8s /]# /bin/bash k8s_imags.sh 
v1.20.2: Pulling from google_containers/kube-apiserver
f398b465657e: Pull complete 
cbcdf8ef32b4: Pull complete 
d4c1448db014: Pull complete 
Digest: sha256:465ba895d578fbc1c6e299e45689381fd01c54400beba9e8f1d7456077411411
Status: Downloaded newer image for registry.aliyuncs.com/google_containers/kube-apiserver:v1.20.2
registry.aliyuncs.com/google_containers/kube-apiserver:v1.20.2
Untagged: registry.aliyuncs.com/google_containers/kube-apiserver:v1.20.2
Untagged: registry.aliyuncs.com/google_containers/kube-apiserver@sha256:465ba895d578fbc1c6e299e45689381fd01c54400beba9e8f1d7456077411411
v1.20.2: Pulling from google_containers/kube-controller-manager
f398b465657e: Already exists 
cbcdf8ef32b4: Already exists 
45385ddeca02: Pull complete 
Digest: sha256:842a071d4ad49b0018f7f7404ac8a4ddfc2bce2ce15b3f8131d89563fda36c9b
Status: Downloaded newer image for registry.aliyuncs.com/google_containers/kube-controller-manager:v1.20.2
registry.aliyuncs.com/google_containers/kube-controller-manager:v1.20.2
Untagged: registry.aliyuncs.com/google_containers/kube-controller-manager:v1.20.2
Untagged: registry.aliyuncs.com/google_containers/kube-controller-manager@sha256:842a071d4ad49b0018f7f7404ac8a4ddfc2bce2ce15b3f8131d89563fda36c9b
v1.20.2: Pulling from google_containers/kube-scheduler
f398b465657e: Already exists 
cbcdf8ef32b4: Already exists 
9c1bb7ba457b: Pull complete 
Digest: sha256:304b3d70497bd62498f19f82f9ef164d38948e5ae94966690abfe9d1858867e2
Status: Downloaded newer image for registry.aliyuncs.com/google_containers/kube-scheduler:v1.20.2
registry.aliyuncs.com/google_containers/kube-scheduler:v1.20.2
Untagged: registry.aliyuncs.com/google_containers/kube-scheduler:v1.20.2
Untagged: registry.aliyuncs.com/google_containers/kube-scheduler@sha256:304b3d70497bd62498f19f82f9ef164d38948e5ae94966690abfe9d1858867e2
v1.20.2: Pulling from google_containers/kube-proxy
e5a8c1ed6cf1: Pull complete 
f275df365c13: Pull complete 
6a2802bb94f4: Pull complete 
cb3853c52da4: Pull complete 
db342cbe4b1c: Pull complete 
9a72dd095a53: Pull complete 
c13a5a64f391: Pull complete 
Digest: sha256:326fe8a4508a5db91cf234c4867eff5ba458bc4107c2a7e15c827a74faa19be9
Status: Downloaded newer image for registry.aliyuncs.com/google_containers/kube-proxy:v1.20.2
registry.aliyuncs.com/google_containers/kube-proxy:v1.20.2
Untagged: registry.aliyuncs.com/google_containers/kube-proxy:v1.20.2
Untagged: registry.aliyuncs.com/google_containers/kube-proxy@sha256:326fe8a4508a5db91cf234c4867eff5ba458bc4107c2a7e15c827a74faa19be9
3.2: Pulling from google_containers/pause
c74f8866df09: Pull complete 
Digest: sha256:927d98197ec1141a368550822d18fa1c60bdae27b78b0c004f705f548c07814f
Status: Downloaded newer image for registry.aliyuncs.com/google_containers/pause:3.2
registry.aliyuncs.com/google_containers/pause:3.2
Untagged: registry.aliyuncs.com/google_containers/pause:3.2
Untagged: registry.aliyuncs.com/google_containers/pause@sha256:927d98197ec1141a368550822d18fa1c60bdae27b78b0c004f705f548c07814f
3.4.13-0: Pulling from google_containers/etcd
4000adbbc3eb: Pull complete 
d72167780652: Pull complete 
d60490a768b5: Pull complete 
4a4b5535d134: Pull complete 
0dac37e8b31a: Pull complete 
Digest: sha256:4ad90a11b55313b182afc186b9876c8e891531b8db4c9bf1541953021618d0e2
Status: Downloaded newer image for registry.aliyuncs.com/google_containers/etcd:3.4.13-0
registry.aliyuncs.com/google_containers/etcd:3.4.13-0
Untagged: registry.aliyuncs.com/google_containers/etcd:3.4.13-0
Untagged: registry.aliyuncs.com/google_containers/etcd@sha256:4ad90a11b55313b182afc186b9876c8e891531b8db4c9bf1541953021618d0e2
1.7.0: Pulling from google_containers/coredns
c6568d217a00: Pull complete 
6937ebe10f02: Pull complete 
Digest: sha256:73ca82b4ce829766d4f1f10947c3a338888f876fbed0540dc849c89ff256e90c
Status: Downloaded newer image for registry.aliyuncs.com/google_containers/coredns:1.7.0
registry.aliyuncs.com/google_containers/coredns:1.7.0
Untagged: registry.aliyuncs.com/google_containers/coredns:1.7.0
Untagged: registry.aliyuncs.com/google_containers/coredns@sha256:73ca82b4ce829766d4f1f10947c3a338888f876fbed0540dc849c89ff256e90c
[root@leoheng-k8s /]#

5.初始化k8s服务

[root@leoheng-k8s ~]# kubeadm init
[init] Using Kubernetes version: v1.20.2
[preflight] Running pre-flight checks
	[WARNING IsDockerSystemdCheck]: detected "cgroupfs" as the Docker cgroup driver. The recommended driver is "systemd". Please follow the guide at https://kubernetes.io/docs/setup/cri/
	[WARNING SystemVerification]: this Docker version is not on the list of validated versions: 20.10.2. Latest validated version: 19.03
	[WARNING Hostname]: hostname "leoheng-k8s" could not be reached
	[WARNING Hostname]: hostname "leoheng-k8s": lookup leoheng-k8s on 100.100.2.138:53: no such host
[preflight] Pulling images required for setting up a Kubernetes cluster
[preflight] This might take a minute or two, depending on the speed of your internet connection
[preflight] You can also perform this action in beforehand using 'kubeadm config images pull'
[certs] Using certificateDir folder "/etc/kubernetes/pki"
[certs] Generating "ca" certificate and key
[certs] Generating "apiserver" certificate and key
[certs] apiserver serving cert is signed for DNS names [kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local leoheng-k8s] and IPs [10.96.0.1 172.18.192.80]
[certs] Generating "apiserver-kubelet-client" certificate and key
[certs] Generating "front-proxy-ca" certificate and key
[certs] Generating "front-proxy-client" certificate and key
[certs] Generating "etcd/ca" certificate and key
[certs] Generating "etcd/server" certificate and key
[certs] etcd/server serving cert is signed for DNS names [leoheng-k8s localhost] and IPs [172.18.192.80 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [leoheng-k8s localhost] and IPs [172.18.192.80 127.0.0.1 ::1]
[certs] Generating "etcd/healthcheck-client" certificate and key
[certs] Generating "apiserver-etcd-client" certificate and key
[certs] Generating "sa" key and public key
[kubeconfig] Using kubeconfig folder "/etc/kubernetes"
[kubeconfig] Writing "admin.conf" kubeconfig file
[kubeconfig] Writing "kubelet.conf" kubeconfig file
[kubeconfig] Writing "controller-manager.conf" kubeconfig file
[kubeconfig] Writing "scheduler.conf" kubeconfig file
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Starting the kubelet
[control-plane] Using manifest folder "/etc/kubernetes/manifests"
[control-plane] Creating static Pod manifest for "kube-apiserver"
[control-plane] Creating static Pod manifest for "kube-controller-manager"
[control-plane] Creating static Pod manifest for "kube-scheduler"
[etcd] Creating static Pod manifest for local etcd in "/etc/kubernetes/manifests"
[wait-control-plane] Waiting for the kubelet to boot up the control plane as static Pods from directory "/etc/kubernetes/manifests". This can take up to 4m0s
[apiclient] All control plane components are healthy after 17.002755 seconds
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config-1.20" in namespace kube-system with the configuration for the kubelets in the cluster
[upload-certs] Skipping phase. Please see --upload-certs
[mark-control-plane] Marking the node leoheng-k8s as control-plane by adding the labels "node-role.kubernetes.io/master=''" and "node-role.kubernetes.io/control-plane='' (deprecated)"
[mark-control-plane] Marking the node leoheng-k8s as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
[bootstrap-token] Using token: 1mxqc0.zwbjh8m8g5d35foe
[bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles
[bootstrap-token] configured RBAC rules to allow Node Bootstrap tokens to get nodes
[bootstrap-token] configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials
[bootstrap-token] configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token
[bootstrap-token] configured RBAC rules to allow certificate rotation for all node client certificates in the cluster
[bootstrap-token] Creating the "cluster-info" ConfigMap in the "kube-public" namespace
[kubelet-finalize] Updating "/etc/kubernetes/kubelet.conf" to point to a rotatable kubelet client certificate and key
[addons] Applied essential addon: CoreDNS
[addons] Applied essential addon: kube-proxy

Your Kubernetes control-plane has initialized successfully!

To start using your cluster, you need to run the following as a regular user:

  mkdir -p $HOME/.kube
  sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
  sudo chown $(id -u):$(id -g) $HOME/.kube/config

Alternatively, if you are the root user, you can run:

  export KUBECONFIG=/etc/kubernetes/admin.conf

You should now deploy a pod network to the cluster.
Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
  https://kubernetes.io/docs/concepts/cluster-administration/addons/

Then you can join any number of worker nodes by running the following on each as root:

kubeadm join 172.18.192.80:6443 --token 1mxqc0.zwbjh8m8g5d35foe \
    --discovery-token-ca-cert-hash sha256:09949a2800da77bd71d046080fe5a75662472a32d0070305ce1fc7457a642b2d

6.启动kubelet并检查服务

[root@leoheng-k8s ~]# systemctl status  kubelet
● kubelet.service - kubelet: The Kubernetes Node Agent
   Loaded: loaded (/usr/lib/systemd/system/kubelet.service; enabled; vendor preset: disabled)
  Drop-In: /usr/lib/systemd/system/kubelet.service.d
           └─10-kubeadm.conf
   Active: active (running) since Thu 2021-01-28 09:58:49 CST; 2min 8s ago
     Docs: https://kubernetes.io/docs/
 Main PID: 4088 (kubelet)
    Tasks: 13
   Memory: 37.8M
   CGroup: /system.slice/kubelet.service
           └─4088 /usr/bin/kubelet --bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf --kubeconfig=/...

Jan 28 10:00:34 leoheng-k8s kubelet[4088]: W0128 10:00:34.351824    4088 cni.go:239] Unable to update cni ...net.d
Jan 28 10:00:36 leoheng-k8s kubelet[4088]: E0128 10:00:36.029903    4088 kubelet.go:2163] Container runtim...lized
Jan 28 10:00:39 leoheng-k8s kubelet[4088]: W0128 10:00:39.352002    4088 cni.go:239] Unable to update cni ...net.d
Jan 28 10:00:41 leoheng-k8s kubelet[4088]: E0128 10:00:41.044753    4088 kubelet.go:2163] Container runtim...lized
Jan 28 10:00:44 leoheng-k8s kubelet[4088]: W0128 10:00:44.352167    4088 cni.go:239] Unable to update cni ...net.d
Jan 28 10:00:46 leoheng-k8s kubelet[4088]: E0128 10:00:46.060000    4088 kubelet.go:2163] Container runtim...lized
Jan 28 10:00:49 leoheng-k8s kubelet[4088]: W0128 10:00:49.352345    4088 cni.go:239] Unable to update cni ...net.d
Jan 28 10:00:51 leoheng-k8s kubelet[4088]: E0128 10:00:51.075055    4088 kubelet.go:2163] Container runtim...lized
Jan 28 10:00:54 leoheng-k8s kubelet[4088]: W0128 10:00:54.352524    4088 cni.go:239] Unable to update cni ...net.d
Jan 28 10:00:56 leoheng-k8s kubelet[4088]: E0128 10:00:56.090169    4088 kubelet.go:2163] Container runtim...lized
Hint: Some lines were ellipsized, use -l to show in full.
[root@leoheng-k8s ~]#

7.启动防火墙，放行必要的端口

[root@leoheng-k8s ~]# systemctl start firewalld 
[root@leoheng-k8s ~]# firewall-cmd --zone=public --add-port=6443/tcp --permanent && firewall-cmd --reload
success
success
[root@leoheng-k8s ~]# firewall-cmd --zone=public --add-port=10250/tcp --permanent && firewall-cmd --reload
success
success
[root@leoheng-k8s ~]#

8.启动单机模式

[root@leoheng-k8s ~]# echo "export KUBECONFIG=/etc/kubernetes/admin.conf" >> ~/.bash_profile
[root@leoheng-k8s ~]# source ~/.bash_profile
[root@leoheng-k8s ~]# kubectl taint nodes --all node-role.kubernetes.io/master-
node/leoheng-k8s untainted
[root@leoheng-k8s ~]# kubectl get nodes
NAME          STATUS     ROLES                  AGE   VERSION
leoheng-k8s   NotReady   control-plane,master   23m   v1.20.2
[root@leoheng-k8s ~]#

9.安装weave网络插件

[root@leoheng-k8s ~]# kubectl apply -f "https://cloud.weave.works/k8s/net?k8s-version=$(kubectl version | base64 | tr -d '\n')"
serviceaccount/weave-net created
clusterrole.rbac.authorization.k8s.io/weave-net created
clusterrolebinding.rbac.authorization.k8s.io/weave-net created
role.rbac.authorization.k8s.io/weave-net created
rolebinding.rbac.authorization.k8s.io/weave-net created
daemonset.apps/weave-net created

10.查看节点状态已经显示“Ready”

[root@leoheng-k8s ~]# kubectl get nodes
NAME          STATUS   ROLES                  AGE   VERSION
leoheng-k8s   Ready    control-plane,master   53m   v1.20.2
[root@leoheng-k8s ~]#

本文作者： Leoheng
本文链接： http://www.leoheng.com/2021/01/31/部署K8S单机环境/
版权声明： Design by leoheng