Centos7 RKE部署高可用k8s集群
作者：互联网
一、RKE介绍
1、介绍：RKE是经过CNCF认证的Kubernetes发行版,并且全部组件完全在Docker容器内运行
Rancher Server只能在使用RKE或K3s安装的Kubernetes集群中运行
2、节点环境准备
firewall-cmd --permanent --add-port=22/tcp firewall-cmd --permanent --add-port=80/tcp firewall-cmd --permanent --add-port=443/tcp firewall-cmd --permanent --add-port=30000-32767/tcp firewall-cmd --permanent --add-port=30000-32767/udp firewall-cmd --reload
2、同步节点时间
yum install ntpdate -y ntpdate time.windows.com
3、安装docker
任何运行Rancher Server的节点上都需要安装Docker
sudo yum install -y yum-utils device-mapper-persistent-data lvm2 sudo yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo sudo yum install docker-ce-18.09.3-3.el7
4、安装kubectl
cat <<EOF > /etc/yum.repos.d/kubernetes.repo [kubernetes] name=Kubernetes baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64 enabled=1 gpgcheck=1 repo_gpgcheck=1 gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg EOF
sudo yum install kubectl
5、安装RKE
Rancher Kubernetes Engine用于构建Kubernetes集群的CLI
下载地址： https://github.com/rancher/rke/releases/tag/v1.1.3
mv rke_linux-amd64 rke chmod +x rke mv rke /usr/local/bin rke
6、安装Helm
Kubernetes的软件包管理工具
下载地址：https://github.com/helm/helm
tar -zxvf helm-v3.3.1-linux-amd64.tar.gz cd linux-amd64 mv helm /usr/local/bin chown -R admin:admin /usr/local/bin/helm helm version
7、配置ssh免密连接
切换成admin用户，在执行rke up命令的主机上执行创建ssh公私钥 并把公钥分发到各个节点上
ssh-keygen -t rsa ssh-copy-id 192.168.112.120 ssh-copy-id 192.168.112.121
8、配置操作系统参数支持k8s集群 (所有节点上都要执行)
sudo swapoff -a sudo vi /etc/sysctl.conf net.ipv4.ip_forward = 1 net.bridge.bridge-nf-call-ip6tables = 1 net.bridge.bridge-nf-call-iptables = 1 sudo sysctl -p
9、使用rke创建集群初始化配置文件
rke config --name cluster.yml
RKE使用一个名为cluster.yml确定如何在集群中的节点上部署Kubernetes
# If you intened to deploy Kubernetes in an air-gapped environment,
# please consult the documentation on how to configure custom RKE images.
nodes:
- address: "192.168.30.110"
port: "22"
internal_address: ""
role: [controlplane,etcd,worker]
hostname_override: "node1"
user: admin
docker_socket: /var/run/docker.sock
ssh_key: ""
ssh_key_path: ~/.ssh/id_rsa
ssh_cert: ""
ssh_cert_path: ""
labels: {}
taints: []
- address: "192.168.30.129"
port: "22"
internal_address: ""
role: [controlplane,etcd,worker]
hostname_override: "node2"
user: admin
docker_socket: /var/run/docker.sock
ssh_key: ""
ssh_key_path: ~/.ssh/id_rsa
ssh_cert: ""
ssh_cert_path: ""
labels: {}
taints: []
- address: "192.168.30.133"
port: "22"
internal_address: ""
role: [controlplane,etcd,worker]
hostname_override: "node3"
user: admin
docker_socket: /var/run/docker.sock
ssh_key: ""
ssh_key_path: ~/.ssh/id_rsa
ssh_cert: ""
ssh_cert_path: ""
labels: {}
taints: []
services:
etcd:
image: ""
extra_args: {}
extra_binds: []
extra_env: []
external_urls: []
ca_cert: ""
cert: ""
key: ""
path: ""
uid: 0
gid: 0
snapshot: null
retention: ""
creation: ""
backup_config: null
kube-api:
image: ""
extra_args: {}
extra_binds: []
extra_env: []
service_cluster_ip_range: 10.43.0.0/16
service_node_port_range: ""
pod_security_policy: false
always_pull_images: false
secrets_encryption_config: null
audit_log: null
admission_configuration: null
event_rate_limit: null
kube-controller:
image: ""
extra_args: {}
extra_binds: []
extra_env: []
cluster_cidr: 10.42.0.0/16
service_cluster_ip_range: 10.43.0.0/16
scheduler:
image: ""
extra_args: {}
extra_binds: []
extra_env: []
kubelet:
image: ""
extra_args: {}
extra_binds: []
extra_env: []
cluster_domain: cluster.local
infra_container_image: ""
cluster_dns_server: 10.43.0.10
fail_swap_on: false
generate_serving_certificate: false
kubeproxy:
image: ""
extra_args: {}
extra_binds: []
extra_env: []
network:
plugin: flannel
options: {}
mtu: 0
node_selector: {}
update_strategy: null
authentication:
strategy: x509
sans: []
webhook: null
addons: ""
addons_include: []
system_images:
etcd: rancher/coreos-etcd:v3.4.3-rancher1
alpine: rancher/rke-tools:v0.1.58
nginx_proxy: rancher/rke-tools:v0.1.58
cert_downloader: rancher/rke-tools:v0.1.58
kubernetes_services_sidecar: rancher/rke-tools:v0.1.58
kubedns: rancher/k8s-dns-kube-dns:1.15.2
dnsmasq: rancher/k8s-dns-dnsmasq-nanny:1.15.2
kubedns_sidecar: rancher/k8s-dns-sidecar:1.15.2
kubedns_autoscaler: rancher/cluster-proportional-autoscaler:1.7.1
coredns: rancher/coredns-coredns:1.6.9
coredns_autoscaler: rancher/cluster-proportional-autoscaler:1.7.1
nodelocal: rancher/k8s-dns-node-cache:1.15.7
kubernetes: rancher/hyperkube:v1.18.3-rancher2
flannel: rancher/coreos-flannel:v0.12.0
flannel_cni: rancher/flannel-cni:v0.3.0-rancher6
calico_node: rancher/calico-node:v3.13.4
calico_cni: rancher/calico-cni:v3.13.4
calico_controllers: rancher/calico-kube-controllers:v3.13.4
calico_ctl: rancher/calico-ctl:v3.13.4
calico_flexvol: rancher/calico-pod2daemon-flexvol:v3.13.4
canal_node: rancher/calico-node:v3.13.4
canal_cni: rancher/calico-cni:v3.13.4
canal_flannel: rancher/coreos-flannel:v0.12.0
canal_flexvol: rancher/calico-pod2daemon-flexvol:v3.13.4
weave_node: weaveworks/weave-kube:2.6.4
weave_cni: weaveworks/weave-npc:2.6.4
pod_infra_container: rancher/pause:3.1
ingress: rancher/nginx-ingress-controller:nginx-0.32.0-rancher1
ingress_backend: rancher/nginx-ingress-controller-defaultbackend:1.5-rancher1
metrics_server: rancher/metrics-server:v0.3.6
windows_pod_infra_container: rancher/kubelet-pause:v0.1.4
ssh_key_path: ~/.ssh/id_rsa
ssh_cert_path: ""
ssh_agent_auth: false
authorization:
mode: rbac
options: {}
ignore_docker_version: null
kubernetes_version: ""
private_registries: []
ingress:
provider: ""
options: {}
node_selector: {}
extra_args: {}
dns_policy: ""
extra_envs: []
extra_volumes: []
extra_volume_mounts: []
update_strategy: null
cluster_name: ""
cloud_provider:
name: ""
prefix_path: ""
addon_job_timeout: 0
bastion_host:
address: ""
port: ""
user: ""
ssh_key: ""
ssh_key_path: ""
ssh_cert: ""
ssh_cert_path: ""
monitoring:
provider: ""
options: {}
node_selector: {}
update_strategy: null
replicas: null
restore:
restore: false
snapshot_name: ""
dns: null
cluster.yaml
10、部署
rke up
11、设置环境变量
export KUBECONFIG=/home/admin/kube_config_cluster.yml mkdir ~/.kube cp kube_config_rancher-cluster.yml ~/.kube/config
通过RKE安装k8s集群成功,启动的时候有些节点启动的比较慢。需要稍微等待一段时间.
二、RKE的环境清理
1、rancher-node-1,2,3中分别执行以下命令
mkdir rancher
cat > rancher/clear.sh << EOF
df -h|grep kubelet |awk -F % '{print $2}'|xargs umount
rm /var/lib/kubelet/* -rf
rm /etc/kubernetes/* -rf
rm /var/lib/rancher/* -rf
rm /var/lib/etcd/* -rf
rm /var/lib/cni/* -rf
rm -rf /var/run/calico
iptables -F && iptables -t nat -F
ip link del flannel.1
docker ps -a|awk '{print $1}'|xargs docker rm -f
docker volume ls|awk '{print $2}'|xargs docker volume rm
rm -rf /var/etcd/
rm -rf /run/kubernetes/
docker rm -fv $(docker ps -aq)
docker volume rm $(docker volume ls)
rm -rf /etc/cni
rm -rf /opt/cni
systemctl restart docker
EOF
sh rancher/clear.sh
清理脚本
2、清理残留目录结束。如果还有问题可能需要卸载所有节点上的docker
首先查看Docker版本 # yum list installed | grep docker docker-ce.x86_64 18.05.0.ce-3.el7.centos @docker-ce-edge 执行卸载 # yum -y remove docker-ce.x86_64 删除存储目录 # rm -rf /etc/docker # rm -rf /run/docker # rm -rf /var/lib/dockershim # rm -rf /var/lib/docker 如果发现删除不掉，需要先 umount，如 # umount /var/lib/docker/devicemapper 卸载docker
rke up --config=./rancher-cluster.yml rke启动执行是幂等操作的 有时候需要多次执行才能成功
3、rke多次安装和卸载k8s集群问题
启动的时候提示ectd的集群健康检查失败
清空节点上所有k8s的相关目录。卸载和删除docker所有相关目录。重新安装docker
最后在执行rke启动命令
三、扩容节点，缩容节点
1、添加节点
修改cluster.yal 将需要添加的节点配置，然后运行
more cluster.yml
nodes:
- address: 172.20.101.103
user: ptmind
role: [controlplane,worker,etcd]
- address: 172.20.101.104
user: ptmind
role: [controlplane,worker,etcd]
- address: 172.20.101.105
user: ptmind
role: [controlplane,worker,etcd]
- address: 172.20.101.106
user: ptmind
role: [worker]
labels: {traefik: traefik-outer}
2、执行添加节点操作
rke up --update-only
3、rke 删除节点
修改cluster.yal 将需要删除的节点配置删除，然后运行
more cluster.yml
nodes:
- address: 172.20.101.103
user: ptmind
role: [controlplane,worker,etcd]
- address: 172.20.101.104
user: ptmind
role: [controlplane,worker,etcd]
- address: 172.20.101.105
user: ptmind
role: [controlplane,worker,etcd]
删除# - address: 172.20.101.106
删除# user: ptmind
删除# role: [worker]
删除# labels: {traefik: traefik-outer}
4、执行删除节点操作
rke up --update-only
问题：当node节点处于NotReady状态下，对节点不可做操作，比如做了删除节点操作，会报错，删除不了节点。
解决办法：
1、手动删除节点上的组件。
2、通过命令移除节点的角色
kubectl label node prod-129 node-role.kubernetes.io/controlplane-
问题：k8s 集群的节点处于 SchedulingDisabled
解决方法：
kubectl patch node NodeName -p "{\"spec\":{\"unschedulable\":false}}"
或者：
设置不可调度 kubectl cordon node07-ingress 取消节点不可调度 kubectl uncordon node07-ingress 驱逐节点的pod kubectl drain --ignore-daemonsets --delete-local-data node07-ingress 删除节点 kubectl delete node node07-ingress
标签：extra,rke,Centos7,RKE,ssh,rancher,docker,k8s,节点 来源： https://www.cnblogs.com/aqicheng/p/14807393.html