• 使用kubeadm搭建高可用k8s v1.16.3集群


    1、部署环境说明

    本文通过kubeadm搭建一个高可用的k8s集群,kubeadm可以帮助我们快速的搭建k8s集群,高可用主要体现在对master节点组件及etcd存储的高可用,文中使用到的服务器ip及角色对应如下:

    主机名称 ip地址 角色
    - 192.168.9.80 虚拟ip(vip)
    k8s-master-01 192.168.9.81 master
    K8s-master-02 192.168.9.82 master
    K8s-master-03 192.168.9.83 master
    k8s-node-01 192.168.9.84 node
    K8s-node-02 192.168.9.85 node
    K8s-node-03 192.168.9.79 node

    2、集群架构及部署准备工作

    2.1、集群架构说明

    前面提到高可用主要体现在master相关组件及etcd,master中apiserver是集群的入口,搭建三个master通过keepalived提供一个vip实现高可用,并且添加haproxy来为apiserver提供反向代理的作用,这样来自haproxy的所有请求都将轮询转发到后端的master节点上。如果仅仅使用keepalived,当集群正常工作时,所有流量还是会到具有vip的那台master上,因此加上了haproxy使整个集群的master都能参与进来,集群的健壮性更强。对应架构图如下所示:

    2.2、修改hosts及hostname

    所有节点修改主机名和hosts文件,文件内容如下

    192.168.9.80    master.k8s.io   k8s-vip
    192.168.9.81    master01.k8s.io k8s-master-01
    192.168.9.82    master02.k8s.io k8s-master-02
    192.168.9.83    master03.k8s.io k8s-master-03
    192.168.9.84    node01.k8s.io   k8s-node-01
    192.168.9.85    node02.k8s.io   k8s-node-02
    192.168.9.79    node03.k8s.io   k8s-node-03
    

    2.3、其他准备

    所有节点操作

    • 主机时间同步
      时间同步可以通过chrony或者ntp来实现,这里不再赘述

    • 关闭防火墙
      关闭centos7自带的firewalld防火墙服务

    • 关闭selinux

    • 禁用swap
      kubeadm会检查当前主机是否禁用了swap,如果启动了 swap将导致安装不能正常进行,所以需要禁用所有的swap

    # 临时关闭
    $ swapoff -a && sysctl -w vm.swappiness=0
    # 永久关闭,在文件中添加注释
    $ vim /etc/fstab
    ...
    UUID=7bf41652-e6e9-415c-8dd9-e112641b220e /boot                   xfs     defaults        0 0
    #/dev/mapper/centos-swap swap                    swap    defaults        0 0
    # 或者利用sed命令完事儿
    $ sed -ri '/^[^#]*swap/s@^@#@' /etc/fstab
    
    • 设置系统其它参数

    开启路由转发

    $ vim /etc/sysctl.d/k8s.conf
    net.ipv4.ip_forward = 1
    net.bridge.bridge-nf-call-ip6tables = 1
    net.bridge.bridge-nf-call-iptables = 1
    $ modprobe br_netfilter
    $ sysctl -p /etc/sysctl.d/k8s.conf
    net.ipv4.ip_forward = 1
    net.bridge.bridge-nf-call-ip6tables = 1
    net.bridge.bridge-nf-call-iptables = 1
    

    设置资源配置文件

    $ echo "* soft nofile 65536" >> /etc/security/limits.conf
    $ echo "* hard nofile 65536" >> /etc/security/limits.conf
    $ echo "* soft nproc 65536"  >> /etc/security/limits.conf
    $ echo "* hard nproc 65536"  >> /etc/security/limits.conf
    $ echo "* soft  memlock  unlimited"  >> /etc/security/limits.conf
    $ echo "* hard memlock  unlimited"  >> /etc/security/limits.conf
    
    • 安装相关包
    $ yum install -y conntrack-tools libseccomp libtool-ltdl
    

    3、部署keepalived

    在三台master操作

    3.1、安装

    $ yum install -y keepalived
    

    3.2、配置

    默认的keepalived配置较复杂,这里用更为简明的方式进行配置,另外的两台master配置和上面类似,只需要修改对应的state配置为BACKUP,priority权重值不同即可,配置中的其他字段这里不做说明。

    k8s-master-01的配置:

    cat > /etc/keepalived/keepalived.conf <<EOF 
    ! Configuration File for keepalived
    
    global_defs {
       router_id k8s
    }
    
    vrrp_script check_haproxy {
        script "killall -0 haproxy"
        interval 3
        weight -2
        fall 10
        rise 2
    }
    
    vrrp_instance VI_1 {
        state MASTER 
        interface eth0 
        virtual_router_id 51
        priority 250
        advert_int 1
        authentication {
            auth_type PASS
            auth_pass ceb1b3ec013d66163d6ab
        }
        virtual_ipaddress {
            192.168.9.80
        }
        track_script {
            check_haproxy
        }
    
    }
    EOF
    

    k8s-master-02的配置:

    cat > /etc/keepalived/keepalived.conf <<EOF 
    ! Configuration File for keepalived
    
    global_defs {
       router_id k8s
    }
    
    vrrp_script check_haproxy {
        script "killall -0 haproxy"
        interval 3
        weight -2
        fall 10
        rise 2
    }
    
    vrrp_instance VI_1 {
        state BACKUP 
        interface eth0 
        virtual_router_id 51
        priority 200
        advert_int 1
        authentication {
            auth_type PASS
            auth_pass ceb1b3ec013d66163d6ab
        }
        virtual_ipaddress {
            192.168.9.80
        }
        track_script {
            check_haproxy
        }
    
    }
    EOF
    

    k8s-master-03的配置:

    cat > /etc/keepalived/keepalived.conf <<EOF 
    ! Configuration File for keepalived
    
    global_defs {
       router_id k8s
    }
    
    vrrp_script check_haproxy {
        script "killall -0 haproxy"
        interval 3
        weight -2
        fall 10
        rise 2
    }
    
    vrrp_instance VI_1 {
        state BACKUP 
        interface eth0 
        virtual_router_id 51
        priority 150
        advert_int 1
        authentication {
            auth_type PASS
            auth_pass ceb1b3ec013d66163d6ab
        }
        virtual_ipaddress {
            192.168.9.80
        }
        track_script {
            check_haproxy
        }
    
    }
    EOF
    

    3.3、启动和检查

    在三台master节点都启动服务

    # 设置开机启动
    $ systemctl enable keepalived.service
    # 启动keepalived
    $ systemctl start keepalived.service
    # 查看启动状态
    $ systemctl status keepalived.service
    

    启动后查看k8s-master-01的网卡信息

    [root@k8s-master-01 ~]# ip a s eth0
    2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
        link/ether 00:0c:29:84:45:8a brd ff:ff:ff:ff:ff:ff
        inet 192.168.9.81/24 brd 192.168.9.255 scope global eth0
           valid_lft forever preferred_lft forever
        inet 192.168.9.80/32 scope global eth0
           valid_lft forever preferred_lft forever
        inet6 fe80::20c:29ff:fe84:458a/64 scope link 
           valid_lft forever preferred_lft forever
    

    尝试停掉k8s-master-01keepalived服务,查看vip是否能漂移到其他的master,并且重新启动k8s-master-01keepalived服务,查看vip是否能正常漂移回来,证明配置没有问题。

    4、部署haproxy

    在三台master操作

    4.1、安装

    $ yum install -y haproxy
    

    4.2、配置

    三台master节点的配置均相同,配置中声明了后端代理的三个master节点服务器,指定了haproxy运行的端口为16443等,因此16443端口为集群的入口,其他的配置不做赘述。

    cat > /etc/haproxy/haproxy.cfg << EOF
    #---------------------------------------------------------------------
    # Global settings
    #---------------------------------------------------------------------
    global
        # to have these messages end up in /var/log/haproxy.log you will
        # need to:
        # 1) configure syslog to accept network log events.  This is done
        #    by adding the '-r' option to the SYSLOGD_OPTIONS in
        #    /etc/sysconfig/syslog
        # 2) configure local2 events to go to the /var/log/haproxy.log
        #   file. A line like the following can be added to
        #   /etc/sysconfig/syslog
        #
        #    local2.*                       /var/log/haproxy.log
        #
        log         127.0.0.1 local2
        
        chroot      /var/lib/haproxy
        pidfile     /var/run/haproxy.pid
        maxconn     4000
        user        haproxy
        group       haproxy
        daemon 
           
        # turn on stats unix socket
        stats socket /var/lib/haproxy/stats
    #---------------------------------------------------------------------
    # common defaults that all the 'listen' and 'backend' sections will
    # use if not designated in their block
    #---------------------------------------------------------------------  
    defaults
        mode                    http
        log                     global
        option                  httplog
        option                  dontlognull
        option http-server-close
        option forwardfor       except 127.0.0.0/8
        option                  redispatch
        retries                 3
        timeout http-request    10s
        timeout queue           1m
        timeout connect         10s
        timeout client          1m
        timeout server          1m
        timeout http-keep-alive 10s
        timeout check           10s
        maxconn                 3000
    #---------------------------------------------------------------------
    # kubernetes apiserver frontend which proxys to the backends
    #--------------------------------------------------------------------- 
    frontend kubernetes-apiserver
        mode                 tcp
        bind                 *:16443
        option               tcplog
        default_backend      kubernetes-apiserver    
    #---------------------------------------------------------------------
    # round robin balancing between the various backends
    #---------------------------------------------------------------------
    backend kubernetes-apiserver
        mode        tcp
        balance     roundrobin
        server      master01.k8s.io   192.168.9.81:6443 check
        server      master02.k8s.io   192.168.9.82:6443 check
        server      master03.k8s.io   192.168.9.83:6443 check
    #---------------------------------------------------------------------
    # collection haproxy statistics message
    #---------------------------------------------------------------------
    listen stats
        bind                 *:1080
        stats auth           admin:awesomePassword
        stats refresh        5s
        stats realm          HAProxy Statistics
        stats uri            /admin?stats
    EOF
    

    4.3、启动和检查

    在三台master节点都启动服务

    # 设置开机启动
    $ systemctl enable haproxy
    # 开启haproxy
    $ systemctl start haproxy
    # 查看启动状态
    $ systemctl status haproxy
    

    检查端口

    [root@k8s-master-01 ~]# netstat -lntup|grep haproxy
    tcp        0      0 0.0.0.0:1080            0.0.0.0:*               LISTEN      7067/haproxy        
    tcp        0      0 0.0.0.0:16443           0.0.0.0:*               LISTEN      7067/haproxy        
    udp        0      0 0.0.0.0:47041           0.0.0.0:*                           7066/haproxy 
    

    5、安装docker

    所有节点操作,使用yum安装,参考阿里云镜像站指导
    今天查看阿里云镜像站时,发现已经全新改版上线了,企业免费做国内开源镜像站,点个赞

    5.1、安装

    # step 1: 安装必要的一些系统工具
    $ yum install -y yum-utils device-mapper-persistent-data lvm2
    # Step 2: 添加软件源信息
    $ sudo yum-config-manager --add-repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
    # Step 3: 查找Docker-CE的版本:
    $ yum list docker-ce.x86_64 --showduplicates | sort -r
    # Step 4: 安装指定版本的Docker-CE
    $ yum makecache fast
    $ yum install -y docker-ce-18.09.9
    

    5.2、配置

    修改docker的配置文件,目前k8s推荐使用的docker文件驱动是systemd,按照k8s官方文档可查看如何配置

    $ vim /etc/docker/daemon.json
    {
      "exec-opts": ["native.cgroupdriver=systemd"],
      "log-driver": "json-file",
      "log-opts": {
        "max-size": "100m"
      },
      "storage-driver": "overlay2",
      "storage-opts": [
        "overlay2.override_kernel_check=true"
      ]
    }
    

    修改docker的服务配置文件,指定docker的数据目录为外挂的磁盘--graph /data/docker

    $ vim /lib/systemd/system/docker.service
    ExecStart=/usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock --graph /data/docker
    

    5.3、启动

    启动docker服务

    $ systemctl daemon-reload
    $ systemctl start docker.service
    $ systemctl enable docker.service
    $ systemctl status docker.service
    

    检查docker信息

    $ docker version
    Client: Docker Engine - Community
     Version:           19.03.5
     API version:       1.39 (downgraded from 1.40)
     Go version:        go1.12.12
     Git commit:        633a0ea
     Built:             Wed Nov 13 07:25:41 2019
     OS/Arch:           linux/amd64
     Experimental:      false
    
    Server: Docker Engine - Community
     Engine:
      Version:          18.09.9
      API version:      1.39 (minimum version 1.12)
      Go version:       go1.11.13
      Git commit:       039a7df
      Built:            Wed Sep  4 16:22:32 2019
      OS/Arch:          linux/amd64
      Experimental:     false
    

    6、安装kubeadm,kubelet和kubectl

    所有节点操作

    6.1、添加阿里云k8s的yum源

    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
    

    6.2、安装

    $ yum install -y kubelet-1.16.3 kubeadm-1.16.3 kubectl-1.16.3
    $ systemctl enable kubelet
    

    6.3、配置kubectl自动补全

    [root@k8s-master-01 ~]# source <(kubectl completion bash)
    [root@k8s-master-01 ~]# echo "source <(kubectl completion bash)" >> ~/.bashrc
    

    7、安装master

    在具有vip的master上操作,这里为k8s-master-01

    7.1、创建kubeadm配置文件

    [root@k8s-master-01 ~]# mkdir /usr/local/kubernetes/manifests -p
    [root@k8s-master-01 ~]# cd /usr/local/kubernetes/manifests/
    [root@k8s-master-01 manifests]# vim kubeadm-config.yaml
    apiServer:
      certSANs:
        - k8s-master-01
        - k8s-master-02
        - k8s-master-03
        - master.k8s.io
        - 192.168.9.80
        - 192.168.9.81
        - 192.168.9.82
        - 192.168.9.83
        - 127.0.0.1
      extraArgs:
        authorization-mode: Node,RBAC
      timeoutForControlPlane: 4m0s
    apiVersion: kubeadm.k8s.io/v1beta1
    certificatesDir: /etc/kubernetes/pki
    clusterName: kubernetes
    controlPlaneEndpoint: "master.k8s.io:16443"
    controllerManager: {}
    dns: 
      type: CoreDNS
    etcd:
      local:    
        dataDir: /var/lib/etcd
    imageRepository: registry.aliyuncs.com/google_containers
    kind: ClusterConfiguration
    kubernetesVersion: v1.16.3
    networking: 
      dnsDomain: cluster.local  
      podSubnet: 10.244.0.0/16
      serviceSubnet: 10.1.0.0/16
    scheduler: {}
    

    7.2、初始化master节点

    [root@k8s-master-01 manifests]# kubeadm init --config kubeadm-config.yaml 
    [init] Using Kubernetes version: v1.16.3
    [preflight] Running pre-flight checks
    [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'
    [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] Activating the kubelet service
    [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 [k8s-master-01 kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local master.k8s.io k8s-master-01 k8s-master-02 k8s-master-03 master.k8s.io] and IPs [10.1.0.1 192.168.9.81 192.168.9.80 192.168.9.81 192.168.9.82 192.168.9.83 127.0.0.1]
    [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 [k8s-master-01 localhost] and IPs [192.168.9.81 127.0.0.1 ::1]
    [certs] Generating "etcd/peer" certificate and key
    [certs] etcd/peer serving cert is signed for DNS names [k8s-master-01 localhost] and IPs [192.168.9.81 127.0.0.1 ::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"
    [endpoint] WARNING: port specified in controlPlaneEndpoint overrides bindPort in the controlplane address
    [kubeconfig] Writing "admin.conf" kubeconfig file
    [endpoint] WARNING: port specified in controlPlaneEndpoint overrides bindPort in the controlplane address
    [kubeconfig] Writing "kubelet.conf" kubeconfig file
    [endpoint] WARNING: port specified in controlPlaneEndpoint overrides bindPort in the controlplane address
    [kubeconfig] Writing "controller-manager.conf" kubeconfig file
    [endpoint] WARNING: port specified in controlPlaneEndpoint overrides bindPort in the controlplane address
    [kubeconfig] Writing "scheduler.conf" kubeconfig file
    [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 21.505682 seconds
    [upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
    [kubelet] Creating a ConfigMap "kubelet-config-1.16" 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 k8s-master-01 as control-plane by adding the label "node-role.kubernetes.io/master=''"
    [mark-control-plane] Marking the node k8s-master-01 as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
    [bootstrap-token] Using token: jv5z7n.3y1zi95p952y9p65
    [bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles
    [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
    [addons] Applied essential addon: CoreDNS
    [endpoint] WARNING: port specified in controlPlaneEndpoint overrides bindPort in the controlplane address
    [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
    
    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/
    
    You can now join any number of control-plane nodes by copying certificate authorities 
    and service account keys on each node and then running the following as root:
    
      kubeadm join master.k8s.io:16443 --token jv5z7n.3y1zi95p952y9p65 
        --discovery-token-ca-cert-hash sha256:403bca185c2f3a4791685013499e7ce58f9848e2213e27194b75a2e3293d8812 
        --control-plane       
    
    Then you can join any number of worker nodes by running the following on each as root:
    
    kubeadm join master.k8s.io:16443 --token jv5z7n.3y1zi95p952y9p65 
        --discovery-token-ca-cert-hash sha256:403bca185c2f3a4791685013499e7ce58f9848e2213e27194b75a2e3293d8812
    

    7.3、按照提示配置环境变量

    [root@k8s-master-01 manifests]# mkdir -p $HOME/.kube
    [root@k8s-master-01 manifests]# sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
    [root@k8s-master-01 manifests]# sudo chown $(id -u):$(id -g) $HOME/.kube/config
    

    7.4、查看集群状态

    [root@k8s-master-01 manifests]# kubectl get cs
    NAME                 AGE
    scheduler            <unknown>
    controller-manager   <unknown>
    etcd-0               <unknown>
    [root@k8s-master-01 manifests]# kubectl get pods -n kube-system
    NAME                                    READY   STATUS    RESTARTS   AGE
    coredns-58cc8c89f4-56n7g                0/1     Pending   0          87s
    coredns-58cc8c89f4-zclz7                0/1     Pending   0          87s
    etcd-k8s-master-01                      1/1     Running   0          18s
    kube-apiserver-k8s-master-01            1/1     Running   0          21s
    kube-controller-manager-k8s-master-01   1/1     Running   0          33s
    kube-proxy-ptjjn                        1/1     Running   0          87s
    kube-scheduler-k8s-master-01            1/1     Running   0          25s
    

    执行kubectl get cs显示<unknown>是一个1.16版本已知的bug,后续官方应该会解决处理,有大佬分析了源码并且提交了pr,可点此参考
    集群默认也把coredns安装了,这里处于pending状态的原因是因为还没有安装网络组件

    8、安装集群网络

    master节点操作

    8.1、获取yaml

    从官方地址获取到flannel的yaml

    [root@k8s-master-01 manifests]# mkdir flannel
    [root@k8s-master-01 manifests]# cd flannel
    [root@k8s-master-01 flannel]# wget -c https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
    

    确保yaml中的pod子网与前面执行kubeadm初始化时相同,yaml中的镜像如果无法获取,可以使用微软中国镜像源代替,例如

    quay.io/coreos/flannel:v0.11.0-amd64  # 源地址
    quay.azk8s.cn/coreos/flannel:v0.11.0-amd64  # 代替
    

    8.2、安装

    [root@k8s-master-01 flannel]# kubectl apply -f kube-flannel.yml 
    podsecuritypolicy.policy/psp.flannel.unprivileged created
    clusterrole.rbac.authorization.k8s.io/flannel created
    clusterrolebinding.rbac.authorization.k8s.io/flannel created
    serviceaccount/flannel created
    configmap/kube-flannel-cfg created
    daemonset.apps/kube-flannel-ds-amd64 created
    daemonset.apps/kube-flannel-ds-arm64 created
    daemonset.apps/kube-flannel-ds-arm created
    daemonset.apps/kube-flannel-ds-ppc64le created
    daemonset.apps/kube-flannel-ds-s390x created
    

    8.3、检查

    [root@k8s-master-01 flannel]# kubectl get pods -n kube-system
    NAME                                    READY   STATUS    RESTARTS   AGE
    coredns-58cc8c89f4-56n7g                1/1     Running   0          20m
    coredns-58cc8c89f4-zclz7                1/1     Running   0          20m
    etcd-k8s-master-01                      1/1     Running   0          19m
    kube-apiserver-k8s-master-01            1/1     Running   0          19m
    kube-controller-manager-k8s-master-01   1/1     Running   0          19m
    kube-flannel-ds-amd64-8d8bc             1/1     Running   0          51s
    kube-proxy-ptjjn                        1/1     Running   0          20m
    kube-scheduler-k8s-master-01            1/1     Running   0          19m
    

    9、其他节点加入集群

    9.1、master加入集群

    9.1.1、复制密钥及相关文件

    在第一次执行init的机器,此处为k8s-master-01上操作
    复制文件到k8s-master-02

    [root@k8s-master-01 ~]# ssh root@192.168.9.82 mkdir -p /etc/kubernetes/pki/etcd
    [root@k8s-master-01 ~]# scp /etc/kubernetes/admin.conf root@192.168.9.82:/etc/kubernetes
    admin.conf                                                                                                                                        100% 5454   465.7KB/s   00:00    
    [root@k8s-master-01 ~]# scp /etc/kubernetes/pki/{ca.*,sa.*,front-proxy-ca.*} root@192.168.9.82:/etc/kubernetes/pki
    ca.crt                                                                                                                                            100% 1025    89.2KB/s   00:00    
    ca.key                                                                                                                                            100% 1675   212.1KB/s   00:00    
    sa.key                                                                                                                                            100% 1679   210.1KB/s   00:00    
    sa.pub                                                                                                                                            100%  451    56.5KB/s   00:00    
    front-proxy-ca.crt                                                                                                                                100% 1038   131.9KB/s   00:00    
    front-proxy-ca.key                                                                                                                                100% 1679   208.3KB/s   00:00    
    [root@k8s-master-01 ~]# scp /etc/kubernetes/pki/etcd/ca.* root@192.168.9.82:/etc/kubernetes/pki/etcd
    ca.crt                                                                                                                                            100% 1017   138.8KB/s   00:00    
    ca.key
    

    复制文件到k8s-master-03

    [root@k8s-master-01 ~]# ssh root@192.168.9.83 mkdir -p /etc/kubernetes/pki/etcd
    [root@k8s-master-01 ~]# scp /etc/kubernetes/admin.conf root@192.168.9.83:/etc/kubernetes
    admin.conf                                                                                                                                        100% 5454   824.2KB/s   00:00    
    [root@k8s-master-01 ~]# scp /etc/kubernetes/pki/{ca.*,sa.*,front-proxy-ca.*} root@192.168.9.83:/etc/kubernetes/pki
    ca.crt                                                                                                                                            100% 1025   144.6KB/s   00:00    
    ca.key                                                                                                                                            100% 1675   218.0KB/s   00:00    
    sa.key                                                                                                                                            100% 1679   245.7KB/s   00:00    
    sa.pub                                                                                                                                            100%  451    57.3KB/s   00:00    
    front-proxy-ca.crt                                                                                                                                100% 1038   132.6KB/s   00:00    
    front-proxy-ca.key                                                                                                                                100% 1679   213.4KB/s   00:00    
    [root@k8s-master-01 ~]# scp /etc/kubernetes/pki/etcd/ca.* root@192.168.9.83:/etc/kubernetes/pki/etcd
    ca.crt                                                                                                                                            100% 1017    55.0KB/s   00:00    
    ca.key
    

    9.1.2、master加入集群

    分别在其他两台master上操作,执行在k8s-master-01上init后输出的join命令,如果找不到了,可以在master01上执行以下命令输出

    [root@k8s-master-01 ~]# kubeadm token create --print-join-command
    kubeadm join master.k8s.io:16443 --token ckf7bs.30576l0okocepg8b     --discovery-token-ca-cert-hash sha256:19afac8b11182f61073e254fb57b9f19ab4d798b70501036fc69ebef46094aba
    

    k8s-master-02上执行join命令,需要带上参数--control-plane表示把master控制节点加入集群

    [root@k8s-master-02 ~]# kubeadm join master.k8s.io:16443 --token ckf7bs.30576l0okocepg8b     --discovery-token-ca-cert-hash sha256:19afac8b11182f61073e254fb57b9f19ab4d798b70501036fc69ebef46094aba --control-plane
    [preflight] Running pre-flight checks
    [preflight] Reading configuration from the cluster...
    [preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -oyaml'
    [preflight] Running pre-flight checks before initializing the new control plane instance
    [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 "apiserver" certificate and key
    [certs] apiserver serving cert is signed for DNS names [k8s-master-02 kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local master.k8s.io k8s-master-01 k8s-master-02 k8s-master-03 master.k8s.io] and IPs [10.1.0.1 192.168.9.82 192.168.9.80 192.168.9.81 192.168.9.82 192.168.9.83 127.0.0.1]
    [certs] Generating "apiserver-kubelet-client" certificate and key
    [certs] Generating "etcd/peer" certificate and key
    [certs] etcd/peer serving cert is signed for DNS names [k8s-master-02 localhost] and IPs [192.168.9.82 127.0.0.1 ::1]
    [certs] Generating "etcd/healthcheck-client" certificate and key
    [certs] Generating "apiserver-etcd-client" certificate and key
    [certs] Generating "etcd/server" certificate and key
    [certs] etcd/server serving cert is signed for DNS names [k8s-master-02 localhost] and IPs [192.168.9.82 127.0.0.1 ::1]
    [certs] Generating "front-proxy-client" certificate and key
    [certs] Valid certificates and keys now exist in "/etc/kubernetes/pki"
    [certs] Using the existing "sa" key
    [kubeconfig] Generating kubeconfig files
    [kubeconfig] Using kubeconfig folder "/etc/kubernetes"
    [endpoint] WARNING: port specified in controlPlaneEndpoint overrides bindPort in the controlplane address
    [kubeconfig] Using existing kubeconfig file: "/etc/kubernetes/admin.conf"
    [kubeconfig] Writing "controller-manager.conf" kubeconfig file
    [kubeconfig] Writing "scheduler.conf" kubeconfig file
    [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"
    [check-etcd] Checking that the etcd cluster is healthy
    [kubelet-start] Downloading configuration for the kubelet from the "kubelet-config-1.16" ConfigMap in the kube-system namespace
    [kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
    [kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
    [kubelet-start] Activating the kubelet service
    [kubelet-start] Waiting for the kubelet to perform the TLS Bootstrap...
    [etcd] Announced new etcd member joining to the existing etcd cluster
    [etcd] Creating static Pod manifest for "etcd"
    [etcd] Waiting for the new etcd member to join the cluster. This can take up to 40s
    {"level":"warn","ts":"2019-11-27T13:33:59.913+0800","caller":"clientv3/retry_interceptor.go:61","msg":"retrying of unary invoker failed","target":"passthrough:///https://192.168.9.82:2379","attempt":0,"error":"rpc error: code = DeadlineExceeded desc = context deadline exceeded"}
    [upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
    [mark-control-plane] Marking the node k8s-master-02 as control-plane by adding the label "node-role.kubernetes.io/master=''"
    [mark-control-plane] Marking the node k8s-master-02 as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
    
    This node has joined the cluster and a new control plane instance was created:
    
    * Certificate signing request was sent to apiserver and approval was received.
    * The Kubelet was informed of the new secure connection details.
    * Control plane (master) label and taint were applied to the new node.
    * The Kubernetes control plane instances scaled up.
    * A new etcd member was added to the local/stacked etcd cluster.
    
    To start administering your cluster from this node, 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
    
    Run 'kubectl get nodes' to see this node join the cluster.
    
    [root@k8s-master-02 ~]# mkdir -p $HOME/.kube
    [root@k8s-master-02 ~]# sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
    [root@k8s-master-02 ~]# sudo chown $(id -u):$(id -g) $HOME/.kube/config
    

    同样的,在k8s-master-03上执行join命令,输出及后续相关的步骤同上

    [root@k8s-master-03 ~]# kubeadm join master.k8s.io:16443 --token ckf7bs.30576l0okocepg8b     --discovery-token-ca-cert-hash sha256:19afac8b11182f61073e254fb57b9f19ab4d798b70501036fc69ebef46094aba --control-plane
    [root@k8s-master-03 ~]# mkdir -p $HOME/.kube
    [root@k8s-master-03 ~]# sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
    [root@k8s-master-03 ~]# sudo chown $(id -u):$(id -g) $HOME/.kube/config
    

    9.1.3、检查

    在其中一台master上执行命令检查集群及pod状态

    [root@k8s-master-01 ~]# kubectl get node
    NAME            STATUS   ROLES    AGE     VERSION
    k8s-master-01   Ready    master   36m     v1.16.3
    k8s-master-02   Ready    master   3m20s   v1.16.3
    k8s-master-03   Ready    master   21s     v1.16.3
    [root@k8s-master-01 ~]# kubectl get pods --all-namespaces
    NAMESPACE     NAME                                    READY   STATUS    RESTARTS   AGE
    kube-system   coredns-58cc8c89f4-56n7g                1/1     Running   0          36m
    kube-system   coredns-58cc8c89f4-zclz7                1/1     Running   0          36m
    kube-system   etcd-k8s-master-01                      1/1     Running   0          35m
    kube-system   etcd-k8s-master-02                      1/1     Running   0          3m55s
    kube-system   etcd-k8s-master-03                      1/1     Running   0          56s
    kube-system   kube-apiserver-k8s-master-01            1/1     Running   0          35m
    kube-system   kube-apiserver-k8s-master-02            1/1     Running   0          3m55s
    kube-system   kube-apiserver-k8s-master-03            1/1     Running   0          57s
    kube-system   kube-controller-manager-k8s-master-01   1/1     Running   1          35m
    kube-system   kube-controller-manager-k8s-master-02   1/1     Running   0          3m55s
    kube-system   kube-controller-manager-k8s-master-03   1/1     Running   0          57s
    kube-system   kube-flannel-ds-amd64-7hnhl             1/1     Running   1          3m56s
    kube-system   kube-flannel-ds-amd64-8d8bc             1/1     Running   0          17m
    kube-system   kube-flannel-ds-amd64-fp2rb             1/1     Running   0          57s
    kube-system   kube-proxy-gzswt                        1/1     Running   0          3m56s
    kube-system   kube-proxy-hdrq7                        1/1     Running   0          57s
    kube-system   kube-proxy-ptjjn                        1/1     Running   0          36m
    kube-system   kube-scheduler-k8s-master-01            1/1     Running   1          35m
    kube-system   kube-scheduler-k8s-master-02            1/1     Running   0          3m55s
    kube-system   kube-scheduler-k8s-master-03            1/1     Running   0          57s
    

    9.2、node加入集群

    9.2.1、node加入集群

    分别在其他三台node节点上操作,执行join命令
    k8s-node-01上操作

    [root@k8s-node-02 ~]# kubeadm join master.k8s.io:16443 --token ckf7bs.30576l0okocepg8b     --discovery-token-ca-cert-hash sha256:19afac8b11182f61073e254fb57b9f19ab4d798b70501036fc69ebef46094aba
    [preflight] Running pre-flight checks
    [preflight] Reading configuration from the cluster...
    [preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -oyaml'
    [kubelet-start] Downloading configuration for the kubelet from the "kubelet-config-1.16" ConfigMap in the kube-system namespace
    [kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
    [kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
    [kubelet-start] Activating the kubelet service
    [kubelet-start] Waiting for the kubelet to perform the TLS Bootstrap...
    
    This node has joined the cluster:
    * Certificate signing request was sent to apiserver and a response was received.
    * The Kubelet was informed of the new secure connection details.
    
    Run 'kubectl get nodes' on the control-plane to see this node join the cluster.
    

    同理

    [root@k8s-node-02 ~]# kubeadm join master.k8s.io:16443 --token ckf7bs.30576l0okocepg8b     --discovery-token-ca-cert-hash sha256:19afac8b11182f61073e254fb57b9f19ab4d798b70501036fc69ebef46094aba
    [root@k8s-node-03 ~]# kubeadm join master.k8s.io:16443 --token ckf7bs.30576l0okocepg8b     --discovery-token-ca-cert-hash sha256:19afac8b11182f61073e254fb57b9f19ab4d798b70501036fc69ebef46094aba
    

    9.2.2、检查

    [root@k8s-master-01 ~]# kubectl get node
    NAME            STATUS   ROLES    AGE    VERSION
    k8s-master-01   Ready    master   42m    v1.16.3
    k8s-master-02   Ready    master   9m3s   v1.16.3
    k8s-master-03   Ready    master   6m4s   v1.16.3
    k8s-node-01     Ready    <none>   31s    v1.16.3
    k8s-node-02     Ready    <none>   28s    v1.16.3
    k8s-node-03     Ready    <none>   38s    v1.16.3
    [root@k8s-master-01 ~]# kubectl get pods --all-namespaces
    NAMESPACE     NAME                                    READY   STATUS    RESTARTS   AGE
    kube-system   coredns-58cc8c89f4-56n7g                1/1     Running   0          41m
    kube-system   coredns-58cc8c89f4-zclz7                1/1     Running   0          41m
    kube-system   etcd-k8s-master-01                      1/1     Running   0          40m
    kube-system   etcd-k8s-master-02                      1/1     Running   0          9m4s
    kube-system   etcd-k8s-master-03                      1/1     Running   0          6m5s
    kube-system   kube-apiserver-k8s-master-01            1/1     Running   0          40m
    kube-system   kube-apiserver-k8s-master-02            1/1     Running   0          9m4s
    kube-system   kube-apiserver-k8s-master-03            1/1     Running   0          6m6s
    kube-system   kube-controller-manager-k8s-master-01   1/1     Running   1          40m
    kube-system   kube-controller-manager-k8s-master-02   1/1     Running   0          9m4s
    kube-system   kube-controller-manager-k8s-master-03   1/1     Running   0          6m6s
    kube-system   kube-flannel-ds-amd64-7hnhl             1/1     Running   1          9m5s
    kube-system   kube-flannel-ds-amd64-8d8bc             1/1     Running   0          22m
    kube-system   kube-flannel-ds-amd64-bwwlx             1/1     Running   0          33s
    kube-system   kube-flannel-ds-amd64-fp2rb             1/1     Running   0          6m6s
    kube-system   kube-flannel-ds-amd64-g9vdj             1/1     Running   0          40s
    kube-system   kube-flannel-ds-amd64-xcbfr             1/1     Running   0          30s
    kube-system   kube-proxy-485dl                        1/1     Running   0          30s
    kube-system   kube-proxy-8p688                        1/1     Running   0          40s
    kube-system   kube-proxy-fdq7c                        1/1     Running   0          33s
    kube-system   kube-proxy-gzswt                        1/1     Running   0          9m5s
    kube-system   kube-proxy-hdrq7                        1/1     Running   0          6m6s
    kube-system   kube-proxy-ptjjn                        1/1     Running   0          41m
    kube-system   kube-scheduler-k8s-master-01            1/1     Running   1          40m
    kube-system   kube-scheduler-k8s-master-02            1/1     Running   0          9m4s
    kube-system   kube-scheduler-k8s-master-03            1/1     Running   0          6m6s
    

    9.3、集群后续扩容

    默认情况下加入集群的token24小时过期,24小时后如果是想要新的node加入到集群,需要重新生成一个token,命令如下

    # 显示获取token列表
    $ kubeadm token list
    # 生成新的token
    $ kubeadm token create
    

    token外,join命令还需要一个sha256的值,通过以下方法计算

    openssl x509 -pubkey -in /etc/kubernetes/pki/ca.crt | openssl rsa -pubin -outform der 2>/dev/null | openssl dgst -sha256 -hex | sed 's/^.* //'
    

    用上面输出的tokensha256的值或者是利用kubeadm token create --print-join-command拼接join命令即可

    10、集群缩容

    master节点

    kubectl drain <node name> --delete-local-data --force --ignore-daemonsets
    kubectl delete node <node name>
    

    node节点

    kubeadm reset
    

    11、安装dashboard

    11.1、部署dashboard

    地址:https://github.com/kubernetes/dashboard
    文档:https://kubernetes.io/docs/tasks/access-application-cluster/web-ui-dashboard/
    部署最新版本v2.0.0-beta6,下载yaml

    [root@k8s-master-01 manifests]# cd /usr/local/kubernetes/manifests/
    [root@k8s-master-01 manifests]# mkdir dashboard
    [root@k8s-master-01 manifests]# cd dashboard/
    [root@k8s-master-01 dashboard]# wget -c https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0-beta6/aio/deploy/recommended.yaml
    # 修改service类型为nodeport
    [root@k8s-master-01 dashboard]# vim recommended.yaml
    ...
    kind: Service
    apiVersion: v1
    metadata:
      labels:
        k8s-app: kubernetes-dashboard
      name: kubernetes-dashboard
      namespace: kubernetes-dashboard
    spec:
      type: NodePort
      ports:
        - port: 443
          targetPort: 8443
          nodePort: 30001
      selector:
        k8s-app: kubernetes-dashboard
    ...
    [root@k8s-master-01 dashboard]# kubectl apply -f recommended.yaml 
    namespace/kubernetes-dashboard created
    serviceaccount/kubernetes-dashboard created
    service/kubernetes-dashboard created
    secret/kubernetes-dashboard-certs created
    secret/kubernetes-dashboard-csrf created
    secret/kubernetes-dashboard-key-holder created
    configmap/kubernetes-dashboard-settings created
    role.rbac.authorization.k8s.io/kubernetes-dashboard created
    clusterrole.rbac.authorization.k8s.io/kubernetes-dashboard created
    rolebinding.rbac.authorization.k8s.io/kubernetes-dashboard created
    clusterrolebinding.rbac.authorization.k8s.io/kubernetes-dashboard created
    deployment.apps/kubernetes-dashboard created
    service/dashboard-metrics-scraper created
    deployment.apps/dashboard-metrics-scraper created
    [root@k8s-master-01 dashboard]# kubectl get pods -n kubernetes-dashboard 
    NAME                                         READY   STATUS    RESTARTS   AGE
    dashboard-metrics-scraper-76585494d8-62vp9   1/1     Running   0          6m47s
    kubernetes-dashboard-b65488c4-5t57x          1/1     Running   0          6m48s
    [root@k8s-master-01 dashboard]# kubectl get svc -n kubernetes-dashboard
    NAME                        TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)         AGE
    dashboard-metrics-scraper   ClusterIP   10.1.207.27    <none>        8000/TCP        7m6s
    kubernetes-dashboard        NodePort    10.1.207.168   <none>        443:30001/TCP   7m7s
    # 在node上通过https://nodeip:30001访问是否正常
    

    11.2、创建service account并绑定默认cluster-admin管理员集群角色

    [root@k8s-master-01 dashboard]# vim dashboard-adminuser.yaml 
    apiVersion: v1
    kind: ServiceAccount
    metadata:
      name: admin-user
      namespace: kubernetes-dashboard
    ---
    apiVersion: rbac.authorization.k8s.io/v1
    kind: ClusterRoleBinding
    metadata:
      name: admin-user
    roleRef:
      apiGroup: rbac.authorization.k8s.io
      kind: ClusterRole
      name: cluster-admin
    subjects:
    - kind: ServiceAccount
      name: admin-user
      namespace: kubernetes-dashboard
    [root@k8s-master-01 dashboard]# kubectl apply -f dashboard-adminuser.yaml 
    serviceaccount/admin-user created
    clusterrolebinding.rbac.authorization.k8s.io/admin-user created
    

    获取token

    [root@k8s-master-01 dashboard]# kubectl -n kubernetes-dashboard describe secret $(kubectl -n kubernetes-dashboard get secret | grep admin-user | awk '{print $1}')
    Name:         admin-user-token-hb5vs
    Namespace:    kubernetes-dashboard
    Labels:       <none>
    Annotations:  kubernetes.io/service-account.name: admin-user
                  kubernetes.io/service-account.uid: d699cd10-82cb-48ac-af7e-e8eea540b46e
    
    Type:  kubernetes.io/service-account-token
    
    Data
    ====
    ca.crt:     1025 bytes
    namespace:  20 bytes
    token:      eyJhbGciOiJSUzI1NiIsImtpZCI6Ing5T2gwbFR2Wk56SG9rR2xVck5BOFhVRnRWVE0wdHhSdndyOXZ3Uk5vYkUifQ.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.OkhaAJ5wLhQA2oR8wNIvEW9UYYtwEOuGQIMa281f42SD5UrJzHBxk1_YeNbTQFKMJHcgeRpLxCy7PyZotLq7S_x_lhrVtg82MPbagu3ofDjlXLKc3pU9R9DqCHyid1rGXA94muNJRRWuI4Vq4DaPEnZ0xjfkep4AVPiOjFTlHXuBa68qRc-XK4dhs95BozVIHwir1W2CWhlNdfgTEY2QYJX0N1WqBQu_UWi3ay3NDLQR6pn1OcsG4xCemHjjsMmrKElZthAAc3r1aUQdCV7YNpSBajCPSSyfbMiU3mOjy1xLipEijFditif3HGXpKyYLkbuOY4dYtZHocWK7bfgGDQ
    

    11.3、使用token登录到dashboard界面

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  • 原文地址:https://www.cnblogs.com/ssgeek/p/11942062.html
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