使用kubeadm安装Kubernetes-v1.20.0集群
1、基础环境准备
1.1、机器说明，共两台机器一台master，一台node节点
| 机器说明 | 机器ip | 系统 |
|---|---|---|
| master | 192.168.80.10 | centos7.9 |
| node | 192.168.80.20 | centos7.9 |
[root@localhost ~]# cat /etc/redhat-release
CentOS Linux release 7.9.2009 (Core)
[root@localhost ~]# rpm -q kernel
kernel-3.10.0-1160.6.1.el7.x86_64
[root@localhost ~]#
1.2、两台机器均配置host
192.168.80.10 kubernetes-master
192.168.80.20 kubernetes-node
1.3、三台机器均操作以下配置
- 关闭
SELINUX
setenforce 0
sed -i 's/SELINUX=enforcing/SELINUX=disabled/g' /etc/selinux/config
- 关闭
swap
swapoff -a
sed -i 's/^[^#].*swap/#&/' /etc/fstab
systemctl daemon-reload
- 关闭
ipv6
echo net.ipv6.conf.all.disable_ipv6=1 >> /etc/sysctl.conf
echo NETWORKING_IPV6=no >> /etc/sysconfig/network
sed -i 's/IPV6INIT=yes/IPV6INIT=no/g' /etc/sysconfig/network-scripts/ifcfg-ens33
sysctl -p
ip a 查看ipv6是否关闭
- 关闭防火墙
systemctl stop firewalld
systemctl disable firewalld
systemctl status firewalld
- 配置将桥接流量传递到iptables并执行生效
cat <<EOF | sudo tee /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sudo sysctl --system
1.4、两台机器均安装docker-ce的v20版本
- 卸载可能存在的旧版docker
sudo yum remove docker \
docker-client \
docker-client-latest \
docker-common \
docker-latest \
docker-latest-logrotate \
docker-logrotate \
docker-engine
- 下载最新版本docker的rpm安装包进行本地安装
docker官网下载最新的安装包
安装包如下
containerd.io-1.4.3-3.1.el7.x86_64.rpm
docker-ce-20.10.0-3.el7.x86_64.rpm
docker-ce-cli-20.10.0-3.el7.x86_64.rpm
docker-ce-rootless-extras-20.10.0-3.el7.x86_64.rpm
本地安装docker
yum localinstall *.rpm -y --nogpgcheck
设置开机启动并启动docker
systemctl enable docker
systemctl start docker
修改docker的cgroupdriver为systemd（默认为cgroups），因kubernetes默认使用的cgroupdriver为systemd（kubernetes自带的推荐使用）
vi /etc/docker/daemon.json
{
"exec-opts":["native.cgroupdriver=systemd"]
}
systemctl restart docker
1.5、master机器设置免登录node（在master上执行以下命令）
ssh-keygen -t rsa (一路默认回车即可)
ssh-copy-id kubernetes-master
ssh-copy-id kubernetes-node
1.6、镜像准备
- 预先从阿里云镜像获取到对应版本的镜像
docker pull registry.aliyuncs.com/google_containers/kube-apiserver:v1.20.0
docker pull registry.aliyuncs.com/google_containers/kube-controller-manager:v1.20.0
docker pull registry.aliyuncs.com/google_containers/kube-scheduler:v1.20.0
docker pull registry.aliyuncs.com/google_containers/kube-proxy:v1.20.0
docker pull registry.aliyuncs.com/google_containers/pause:3.2
docker pull registry.aliyuncs.com/google_containers/etcd:3.4.13-0
docker pull registry.aliyuncs.com/google_containers/coredns:1.7.0
拿下来后统一改名（master节点需要以下所有镜像）
docker tag registry.aliyuncs.com/google_containers/kube-apiserver:v1.20.0 k8s.gcr.io/kube-apiserver:v1.20.0
docker tag registry.aliyuncs.com/google_containers/kube-controller-manager:v1.20.0 k8s.gcr.io/kube-controller-manager:v1.20.0
docker tag registry.aliyuncs.com/google_containers/kube-scheduler:v1.20.0 k8s.gcr.io/kube-scheduler:v1.20.0
docker tag registry.aliyuncs.com/google_containers/kube-proxy:v1.20.0 k8s.gcr.io/kube-proxy:v1.20.0
docker tag registry.aliyuncs.com/google_containers/pause:3.2 k8s.gcr.io/pause:3.2
docker tag registry.aliyuncs.com/google_containers/etcd:3.4.13-0 k8s.gcr.io/etcd:3.4.13-0
docker tag registry.aliyuncs.com/google_containers/coredns:1.7.0 k8s.gcr.io/coredns:1.7.0
- 另使用calico网络插件，所需依赖的镜像国内网络环境可自动下载
docker.io/calico/cni:v3.17.1
docker.io/calico/pod2daemon-flexvol:v3.17.1
docker.io/calico/node:v3.17.1
docker.io/calico/kube-controllers:v3.17.1
1.7、 kubernetes安装包下载
- 下载的安装包如下
1281489661f7627c8b175b789d300fe3c703c8dd1f618dcdfeac1354131b376d-kubectl-1.20.0-0.x86_64.rpm
14bfe6e75a9efc8eca3f638eb22c7e2ce759c67f95b43b16fae4ebabde1549f3-cri-tools-1.13.0-0.x86_64.rpm
268447fe89ce41034f21c7a6c73290bd2e1920f856ec413285a5054260625822-kubelet-1.20.0-0.x86_64.rpm
91e0f0a3a10ab757acf9611e8b81e1b272d76a5c400544a254d2c34a6ede1c11-kubeadm-1.20.0-0.x86_64.rpm
db7cb5cb0b3f6875f54d10f02e625573988e3e91fd4fc5eef0b1876bb18604ad-kubernetes-cni-0.8.7-0.x86_64.rpm
2、master安装
2.1、 导入镜像(此tar镜像为单独下载并导出以作离线安装使用)
可使用
kubeadm config images list --kubernetes-version=1.20.0检查安装所依赖的镜像
docker load < calico+cni:v3.17.1.tar
docker load < calico+kube-controllers:v3.17.1.tar
docker load < calico+node:v3.17.1.tar
docker load < calico+pod2daemon-flexvol:v3.17.1.tar
docker load < k8s.gcr.io+coredns:1.7.0.tar
docker load < k8s.gcr.io+etcd:3.4.13-0.tar
docker load < k8s.gcr.io+kube-apiserver:v1.20.0.tar
docker load < k8s.gcr.io+kube-controller-manager:v1.20.0.tar
docker load < k8s.gcr.io+kube-proxy:v1.20.0.tar
docker load < k8s.gcr.io+kube-scheduler:v1.20.0.tar
docker load < k8s.gcr.io+pause:3.2.tar
docker tag 183b53858d7d calico/node:v3.17.1
docker tag 740bdc760424 calico/pod2daemon-flexvol:v3.17.1
docker tag 29b6bcc4a8b4 calico/cni:v3.17.1
docker tag 278f40d9f3b8 calico/kube-controllers:v3.17.1
docker tag 10cc881966cf k8s.gcr.io/kube-proxy:v1.20.0
docker tag 3138b6e3d471 k8s.gcr.io/kube-scheduler:v1.20.0
docker tag b9fa1895dcaa k8s.gcr.io/kube-controller-manager:v1.20.0
docker tag ca9843d3b545 k8s.gcr.io/kube-apiserver:v1.20.0
docker tag 0369cf4303ff k8s.gcr.io/etcd:3.4.13-0
docker tag bfe3a36ebd25 k8s.gcr.io/coredns:1.7.0
docker tag 80d28bedfe5d k8s.gcr.io/pause:3.2
2.2、安装kubeadm kubectl kubelet
[root@kubernetes-master software]# ls *.rpm
1281489661f7627c8b175b789d300fe3c703c8dd1f618dcdfeac1354131b376d-kubectl-1.20.0-0.x86_64.rpm
14bfe6e75a9efc8eca3f638eb22c7e2ce759c67f95b43b16fae4ebabde1549f3-cri-tools-1.13.0-0.x86_64.rpm
268447fe89ce41034f21c7a6c73290bd2e1920f856ec413285a5054260625822-kubelet-1.20.0-0.x86_64.rpm
91e0f0a3a10ab757acf9611e8b81e1b272d76a5c400544a254d2c34a6ede1c11-kubeadm-1.20.0-0.x86_64.rpm
db7cb5cb0b3f6875f54d10f02e625573988e3e91fd4fc5eef0b1876bb18604ad-kubernetes-cni-0.8.7-0.x86_64.rpm
[root@kubernetes-master software]# yum localinstall *.rpm -y --nogpgcheck
使用命令
kubeadm config images list可查看所依赖的镜像
2.3、初始化master
kubeadm init
- 按提示初始化完执行命令
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
- 按提示打印出节点加入的方法
kubeadm join 192.168.80.10:6443 --token 945iyw.ejofmbm5mi1rbong \
--discovery-token-ca-cert-hash sha256:2835ace5eed724587d0467a789a0b902a917f27959203a1a5e8428e38e125f2a
可通过
kubeadm token list查看当前的token，默认有效期为24小时，若忘记token或token过期，可使用命令kubeadm token create --print-join-command重新生成，若初始有问题可通过命令kubeadm reset重置。
2.4、启动kubelet并检查状态
systemctl start kubelet
systemctl status kubelet
若启动出错，可使用命令
journalctl -xefu kubelet跟踪错误信息
出现
kubelet cgroup driver: "cgroupfs" is different from docker cgroup driver: "systemd"需修改k8s配置文件指定cgroup为systemd，修改配置文件/usr/lib/systemd/system/kubelet.service.d/10-kubeadm.conf，在KUBELET_KUBECONFIG_ARGS参数增加配置--cgroup-driver=systemd，修改配置文件/var/lib/kubelet/kubeadm-flags.env，在KUBELET_KUBEADM_ARGS参数增加配置--cgroup-driver=systemd，修改完后执行systemctl daemon-reload ; systemctl restart docker kubelet
2.5、查看集群节点状态
[root@kubernetes-master images]# kubectl get node
NAME STATUS ROLES AGE VERSION
kubernetes-master NotReady control-plane,master 2m57s v1.20.0
可以看到master节点是NotReady状态
2.6、安装calico网络插件
可使用命令
grep image calico.yaml查看calico所需的镜像
- 安装calico命令
kubectl apply -f calico.yaml
安装完成后即可看到master为Ready状态
[root@kubernetes-master yaml]# kubectl get node
NAME STATUS ROLES AGE VERSION
kubernetes-master Ready control-plane,master 4m5s v1.20.0
2.7、检查组件状态(kubectl get cs|kubectl get componentstatus)
[root@kubernetes-master yaml]# kubectl get node
NAME STATUS ROLES AGE VERSION
kubernetes-master Ready control-plane,master 4m5s v1.20.0
[root@kubernetes-master yaml]# kubectl get cs|kubectl get componentstatus
Warning: v1 ComponentStatus is deprecated in v1.19+
Warning: v1 ComponentStatus is deprecated in v1.19+
NAME STATUS MESSAGE ERROR
scheduler Unhealthy Get "http://127.0.0.1:10251/healthz": dial tcp 127.0.0.1:10251: connect: connection refused
controller-manager Unhealthy Get "http://127.0.0.1:10252/healthz": dial tcp 127.0.0.1:10252: connect: connection refused
etcd-0 Healthy {"health":"true"}
[root@kubernetes-master yaml]#
可以看到scheduler与controller-manager是Unhealthy的，按端口提示检查10251及10252是否有监听
ss -ant|grep 10251
ss -ant|grep 10252
发现均未有监听，检查配置文件
/etc/kubernetes/manifests/kube-scheduler.yaml与/etc/kubernetes/manifests/kube-controller-manager.yaml并将两个配置文件的配置项- --port=0均注释掉，并重启kubelet，重新检查组件状态
[root@kubernetes-master ~]# systemctl restart kubelet
[root@kubernetes-master ~]# kubectl get cs
Warning: v1 ComponentStatus is deprecated in v1.19+
NAME STATUS MESSAGE ERROR
etcd-0 Healthy {"health":"true"}
controller-manager Healthy ok
scheduler Healthy ok
[root@kubernetes-master ~]#
3、node安装
3.1 导入节点所需的镜像
docker load < calico+cni:v3.17.1.tar
docker load < calico+kube-controllers:v3.17.1.tar
docker load < calico+node:v3.17.1.tar
docker load < calico+pod2daemon-flexvol:v3.17.1.tar
docker load < k8s.gcr.io+kube-proxy:v1.20.0.tar
docker load < k8s.gcr.io+pause:3.2.tar
docker tag 183b53858d7d calico/node:v3.17.1
docker tag 740bdc760424 calico/pod2daemon-flexvol:v3.17.1
docker tag 29b6bcc4a8b4 calico/cni:v3.17.1
docker tag 278f40d9f3b8 calico/kube-controllers:v3.17.1
docker tag 10cc881966cf k8s.gcr.io/kube-proxy:v1.20.0
docker tag 80d28bedfe5d k8s.gcr.io/pause:3.2
3.2 安装kubeadm kubectl kubelet
[root@kubernetes-master software]# ls *.rpm
1281489661f7627c8b175b789d300fe3c703c8dd1f618dcdfeac1354131b376d-kubectl-1.20.0-0.x86_64.rpm
14bfe6e75a9efc8eca3f638eb22c7e2ce759c67f95b43b16fae4ebabde1549f3-cri-tools-1.13.0-0.x86_64.rpm
268447fe89ce41034f21c7a6c73290bd2e1920f856ec413285a5054260625822-kubelet-1.20.0-0.x86_64.rpm
91e0f0a3a10ab757acf9611e8b81e1b272d76a5c400544a254d2c34a6ede1c11-kubeadm-1.20.0-0.x86_64.rpm
db7cb5cb0b3f6875f54d10f02e625573988e3e91fd4fc5eef0b1876bb18604ad-kubernetes-cni-0.8.7-0.x86_64.rpm
[root@kubernetes-master software]# yum localinstall *.rpm -y --nogpgcheck
3.3 启动kubelet并加入集群
kubeadm join 192.168.80.10:6443 --token yke737.yvu9ciyi09hdkscz --discovery-token-ca-cert-hash sha256:2835ace5eed724587d0467a789a0b902a917f27959203a1a5e8428e38e125f2a
4、集群检查
4.1、检查节点
[root@kubernetes-master ~]# kubectl get node
NAME STATUS ROLES AGE VERSION
kubernetes-master Ready control-plane,master 23m v1.20.0
kubernetes-node Ready <none> 41s v1.20.0
[root@kubernetes-master ~]#
4.2、检查基础应用
[root@kubernetes-master ~]# kubectl get po -A
NAMESPACE NAME READY STATUS RESTARTS AGE
kube-system calico-kube-controllers-744cfdf676-b2825 1/1 Running 0 19m
kube-system calico-node-7klv6 1/1 Running 0 19m
kube-system calico-node-ppn6h 1/1 Running 0 65s
kube-system coredns-74ff55c5b-7q5r9 1/1 Running 0 23m
kube-system coredns-74ff55c5b-w8hwt 1/1 Running 0 23m
kube-system etcd-kubernetes-master 1/1 Running 0 23m
kube-system kube-apiserver-kubernetes-master 1/1 Running 0 23m
kube-system kube-controller-manager-kubernetes-master 1/1 Running 0 16m
kube-system kube-proxy-mtzb9 1/1 Running 0 65s
kube-system kube-proxy-sgfnw 1/1 Running 0 23m
kube-system kube-scheduler-kubernetes-master 1/1 Running 0 17m
[root@kubernetes-master ~]#
