在线安装Microk8s
1、安装snap
yum install -y epel-release
yum install -y snapd
systemctl enable --now snapd.socket
systemctl start snapd
ln -s /var/lib/snapd/snap /snap
2、安装microk8s
snap install microk8s --classic # 在RockyLinux9.4上, 默认下载Microk8s 1.31版本
snap install microk8s --classic --channel=1.31/stable # --channnel参数可以指定Microk8s的版本
snap alias microk8s.kubectl kubectl
3、安装microk8s插件(addons)
microk8s enable dns ingress metrics-server
成功安装后，通过kubectl查看Pod和Image
# kubectl get pods -A
kube-system calico-node-srvfr 1/1 Running 0 11m
kube-system calico-kube-controllers-5b577d865-xwqjh 1/1 Running 0 11m
kube-system coredns-64c6478b6c-fcvkk 1/1 Running 0 23s
ingress nginx-ingress-microk8s-controller-rqtj2 1/1 Running 0 32s
kube-system metrics-server-679c5f986d-vb6z7 1/1 Running 0 53mmicrok8s.ctr i list | grep -vw DIGEST | grep -v ^sha256 | grep -v @sha256 | awk '{print $1}'
coredns/coredns:1.10.1
docker.io/calico/cni:v3.25.1
docker.io/calico/kube-controllers:v3.25.1
docker.io/calico/node:v3.25.1
docker.io/coredns/coredns:1.10.1
registry.k8s.io/ingress-nginx/controller:v1.11.2
registry.k8s.io/metrics-server/metrics-server:v0.6.3
registry.k8s.io/pause:3.7
在线安装可能遇到的问题
问题1: pod启动失败, 通过kubectl -n kube-system describe pod 查到失败原因是下载镜像失败
解决方法: 使用microk8s.ctr从国内源下载镜像，再给镜像打个tag，需要下载的镜像如下：
k8s.gcr.io/pause:3.7
docker.io/calico/cni:v3.25.1
docker.io/calico/node:v3.25.1
docker.io/calico/kube-controllers:v3.25.1
docker.io/coredns/coredns:1.10.1
registry.k8s.io/ingress-nginx/controller:v1.11.2
registry.k8s.io/metrics-server/metrics-server:v0.6.3
从国内源下载镜像，再给镜像打tag
microk8s.ctr images pull swr.cn-north-4.myhuaweicloud.com/ddn-k8s/registry.k8s.io/pause:3.7
microk8s.ctr images tag swr.cn-north-4.myhuaweicloud.com/ddn-k8s/registry.k8s.io/pause:3.7 registry.k8s.io/pause:3.7microk8s.ctr images pull swr.cn-north-4.myhuaweicloud.com/ddn-k8s/docker.io/calico/cni:v3.25.1
microk8s.ctr images tag swr.cn-north-4.myhuaweicloud.com/ddn-k8s/docker.io/calico/cni:v3.25.1 docker.io/calico/cni:v3.25.1microk8s.ctr images pull swr.cn-north-4.myhuaweicloud.com/ddn-k8s/docker.io/calico/node:v3.25.1
microk8s.ctr images tag swr.cn-north-4.myhuaweicloud.com/ddn-k8s/docker.io/calico/node:v3.25.1 docker.io/calico/node:v3.25.1microk8s.ctr images pull swr.cn-north-4.myhuaweicloud.com/ddn-k8s/docker.io/calico/kube-controllers:v3.25.1
microk8s.ctr images tag swr.cn-north-4.myhuaweicloud.com/ddn-k8s/docker.io/calico/kube-controllers:v3.25.1 docker.io/calico/kube-controllers:v3.25.1microk8s.ctr images pull swr.cn-north-4.myhuaweicloud.com/ddn-k8s/registry.k8s.io/coredns/coredns:v1.10.1
microk8s.ctr images tag swr.cn-north-4.myhuaweicloud.com/ddn-k8s/registry.k8s.io/coredns/coredns:v1.10.1 docker.io/coredns/coredns:1.10.1microk8s.ctr images pull swr.cn-north-4.myhuaweicloud.com/ddn-k8s/registry.k8s.io/ingress-nginx/controller:v1.11.2
microk8s.ctr images tag swr.cn-north-4.myhuaweicloud.com/ddn-k8s/registry.k8s.io/ingress-nginx/controller:v1.11.2 registry.k8s.io/ingress-nginx/controller:v1.11.2microk8s.ctr images pull swr.cn-north-4.myhuaweicloud.com/ddn-k8s/registry.k8s.io/metrics-server/metrics-server:v0.6.3
microk8s.ctr images tag swr.cn-north-4.myhuaweicloud.com/ddn-k8s/registry.k8s.io/metrics-server/metrics-server:v0.6.3 registry.k8s.io/metrics-server/metrics-server:v0.6.3
问题2: metrics-server启动失败, 'dial tcp XXX:10250: connect: no route to host"
解决方法：关闭防火墙，禁用SELinux
systemctl disable firewalld --now
setenforce 0
vim /etc/selinux/config
SELINX=enforcing这行改成SELINUX=permissive
离线安装Microk8s
1、在可联网的环境下载Microk8s的snap安装包
snap download microk8s --channel=1.31/stable # 下载指定版本1.31
2、将下载好的snap包传输到目标机器上，安装microk8s
snap ack microk8s_<版本号>.assert
snap install microk8s_<版本号>.snap --classic
3、启动Microk8s服务
microk8s start
4、在可联网的环境下载Microk8s插件的Image并导出
microk8s.ctr i list | grep -vw DIGEST | grep -v ^sha256 | grep -v @sha256 | awk '{print $1}'
k8s.gcr.io/pause:3.7
docker.io/calico/cni:v3.25.1
docker.io/calico/node:v3.25.1
docker.io/calico/kube-controllers:v3.25.1
docker.io/coredns/coredns:1.10.1
registry.k8s.io/ingress-nginx/controller:v1.11.2
registry.k8s.io/metrics-server/metrics-server:v0.6.3microk8s.ctr i export cni.tar docker.io/calico/cni:v3.25.1
microk8s.ctr i export kube-controllers.tar docker.io/calico/kube-controllers:v3.25.1
microk8s.ctr i export .....
5、将image传到目标机器上并导入
microk8s.ctr image import *.tar
6、启动microk8s插件
microk8s enable dns ingress metrics-server
microk8s status --wait-ready
7、配置kubectl访问Microk8s
microk8s.kubectl config view --raw > $HOME/.kube/config
卸载microk8s
microk8s stop
snap remove microk8s
rm -rf /root/.kube