kubeadm安装的Kubernetes etcd备份恢复

Bertha 。 2022-05-12 13:10 134阅读 0赞

# kubeadm安装的Kubernetes etcd备份恢复 #

### 文章目录 ###

*  kubeadm安装的Kubernetes etcd备份恢复
 *   *  1. 事件由来
     *  2. 环境说明
     *  3. etcd集群查看
     *  4. etcd数据备份
     *  5. etcd数据恢复
     *  6. 小结

## 1. 事件由来 ##

2018年9月16日台风过后，我的一套kuernetes测试系统，etcd启动失败，经过半天的抢救，仍然无果（3台master都是如下错误）。无奈再花半天时间把环境重新弄了起来。即使是etcd集群，备份也是必须的，因为数据没了，就都没了。好在问题出现得早，要是正式生产出现这种情况，估计要卷铺盖走人了。因此，研究下kubernetes备份。

2018-09-17 00:11:55.781279 I | etcdmain: etcd Version: 3.2.18
    2018-09-17 00:11:55.781457 I | etcdmain: Git SHA: eddf599c6
    2018-09-17 00:11:55.781477 I | etcdmain: Go Version: go1.8.7
    2018-09-17 00:11:55.781503 I | etcdmain: Go OS/Arch: linux/amd64
    2018-09-17 00:11:55.781519 I | etcdmain: setting maximum number of CPUs to 32, total number of available CPUs is 32
    2018-09-17 00:11:55.781634 N | etcdmain: the server is already initialized as member before, starting as etcd member...
    2018-09-17 00:11:55.781702 I | embed: peerTLS: cert = /etc/kubernetes/pki/etcd/peer.crt, key = /etc/kubernetes/pki/etcd/peer.key, ca = , trusted-ca = /etc/kubernetes/pki/etcd/ca.crt, client-cert-auth = true
    2018-09-17 00:11:55.783073 I | embed: listening for peers on https://192.168.105.92:2380
    2018-09-17 00:11:55.783182 I | embed: listening for client requests on 127.0.0.1:2379
    2018-09-17 00:11:55.783281 I | embed: listening for client requests on 192.168.105.92:2379
    2018-09-17 00:11:55.791474 I | etcdserver: recovered store from snapshot at index 16471696
    2018-09-17 00:11:55.792633 I | mvcc: restore compact to 13683366
    2018-09-17 00:11:55.849153 C | mvcc: store.keyindex: put with unexpected smaller revision [{13685569 0} / {13685569 0}]
    panic: store.keyindex: put with unexpected smaller revision [{13685569 0} / {13685569 0}]
    
    goroutine 89 [running]:
    github.com/coreos/etcd/cmd/vendor/github.com/coreos/pkg/capnslog.(*PackageLogger).Panicf(0xc42018c160, 0xfa564e, 0x3e, 0xc420062cb0, 0x2, 0x2)
    /tmp/etcd/release/etcd/gopath/src/github.com/coreos/etcd/cmd/vendor/github.com/coreos/pkg/capnslog/pkg_logger.go:75 +0x15c
    github.com/coreos/etcd/cmd/vendor/github.com/coreos/etcd/mvcc.(*keyIndex).put(0xc4207fd7c0, 0xd0d341, 0x0)
    /tmp/etcd/release/etcd/gopath/src/github.com/coreos/etcd/cmd/vendor/github.com/coreos/etcd/mvcc/key_index.go:80 +0x3ec
    github.com/coreos/etcd/cmd/vendor/github.com/coreos/etcd/mvcc.restoreIntoIndex.func1(0xc42029e460, 0xc4202a0600, 0x14bef40, 0xc420285640)
    /tmp/etcd/release/etcd/gopath/src/github.com/coreos/etcd/cmd/vendor/github.com/coreos/etcd/mvcc/kvstore.go:367 +0x3e3
    created by github.com/coreos/etcd/cmd/vendor/github.com/coreos/etcd/mvcc.restoreIntoIndex
    /tmp/etcd/release/etcd/gopath/src/github.com/coreos/etcd/cmd/vendor/github.com/coreos/etcd/mvcc/kvstore.go:374 +0xa5

## 2. 环境说明 ##

kubeadm安装的kubernetes1.11

## 3. etcd集群查看 ##

# 列出成员
    etcdctl --endpoints=https://192.168.105.92:2379,https://192.168.105.93:2379,https://192.168.105.94:2379 --cert-file=/etc/kubernetes/pki/etcd/server.crt  --key-file=/etc/kubernetes/pki/etcd/server.key --ca-file=/etc/kubernetes/pki/etcd/ca.crt member list
    # 列出kubernetes数据
    export ETCDCTL_API=3
    etcdctl get / --prefix --keys-only --cert=/etc/kubernetes/pki/etcd/server.crt --key=/etc/kubernetes/pki/etcd/server.key --cacert=/etc/kubernetes/pki/etcd/ca.crt

## 4. etcd数据备份 ##

*  备份 `/etc/kubernetes/` 目录下的所有文件(证书，manifest文件)
 *  `/var/lib/kubelet/` 目录下所有文件(plugins容器连接认证)
 *  etcd V3版api数据

将脚本添加到计划任务，每日备份。

#!/usr/bin/env bash
    ##############################################################
    # File Name: ut_backup_k8s.sh
    # Version: V1.0
    # Author: Chinge_Yang
    # Blog: http://blog.csdn.net/ygqygq2
    # Created Time : 2018-09-18 09:13:55
    # Description:
    ##############################################################
    
    #获取脚本所存放目录
    cd `dirname $0`
    bash_path=`pwd`
    
    #脚本名
    me=$(basename $0)
    # delete dir and keep days
    delete_dirs=("/data/backup/kubernetes:7")
    backup_dir=/data/backup/kubernetes
    files_dir=("/etc/kubernetes" "/var/lib/kubelet")
    log_dir=$backup_dir/log
    shell_log=$log_dir/${USER}_${me}.log
    ssh_port="22"
    ssh_parameters="-o StrictHostKeyChecking=no -o ConnectTimeout=60"
    ssh_command="ssh ${ssh_parameters} -p ${ssh_port}"
    scp_command="scp ${ssh_parameters} -P ${ssh_port}"
    DATE=$(date +%F)
    BACK_SERVER="127.0.0.1"  # 远程备份服务器IP
    BACK_SERVER_BASE_DIR="/data/backup"
    BACK_SERVER_DIR="$BACK_SERVER_BASE_DIR/kubernetes/${HOSTNAME}"  # 远程备份服务器目录
    BACK_SERVER_LOG_DIR="$BACK_SERVER_BASE_DIR/kubernetes/logs"
    
    #定义保存日志函数
    function save_log () { 
        echo -e "`date +%F\ %T` $*" >> $shell_log
    }
    
    save_log "start backup mysql"
    
    [ ! -d $log_dir ] && mkdir -p $log_dir
    
    #定义输出颜色函数
    function red_echo () { 
    #用法: red_echo "内容"
        local what=$*
        echo -e "\e[1;31m ${what} \e[0m"
    }
    
    function green_echo () { 
    #用法: green_echo "内容"
        local what=$*
        echo -e "\e[1;32m ${what} \e[0m"
    }
    
    function yellow_echo () { 
    #用法: yellow_echo "内容"
        local what=$*
        echo -e "\e[1;33m ${what} \e[0m"
    }
    
    function twinkle_echo () { 
    #用法: twinkle_echo $(red_echo "内容") ,此处例子为红色闪烁输出
        local twinkle='\e[05m'
        local what="${twinkle} $*"
        echo -e "${what}"
    }
    
    function return_echo () { 
        [ $? -eq 0 ] && green_echo "$* 成功" || red_echo "$* 失败" 
    }
    
    function return_error_exit () { 
        [ $? -eq 0 ] && REVAL="0"
        local what=$*
        if [ "$REVAL" = "0" ];then
            [ ! -z "$what" ] && green_echo "$what 成功"
        else
            red_echo "$* 失败，脚本退出"
            exit 1
        fi
    }
    
    #定义确认函数
    function user_verify_function () { 
        while true;do
            echo ""
            read -p "是否确认?[Y/N]:" Y
            case $Y in
        [yY]|[yY][eE][sS])
            echo -e "answer: \\033[20G [ \e[1;32m是\e[0m ] \033[0m"
            break   
            ;;
        [nN]|[nN][oO])
            echo -e "answer: \\033[20G [ \e[1;32m否\e[0m ] \033[0m"          
            exit 1
            ;;
          *)
            continue
            ;;
            esac
        done
    }
    
    #定义跳过函数
    function user_pass_function () { 
        while true;do
            echo ""
            read -p "是否确认?[Y/N]:" Y
            case $Y in
                [yY]|[yY][eE][sS])
                echo -e "answer: \\033[20G [ \e[1;32m是\e[0m ] \033[0m"
                break   
                ;;
                [nN]|[nN][oO])
                echo -e "answer: \\033[20G [ \e[1;32m否\e[0m ] \033[0m"          
                return 1
                ;;
                *)
                continue
                ;;
                esac
        done
    }
    
    function backup () { 
        for f_d in ${files_dir[@]}; do
            f_name=$(basename ${ f_d})
            d_name=$(dirname $f_d)
            cd $d_name
            tar -cjf ${f_name}.tar.bz $f_name
            if [ $? -eq 0 ]; then
                file_size=$(du ${ f_name}.tar.bz|awk '{print $1}')
                save_log "$file_size ${f_name}.tar.bz"
                save_log "finish tar ${f_name}.tar.bz"
            else
                file_size=0
                save_log "failed tar ${f_name}.tar.bz"
            fi
            rsync -avzP ${f_name}.tar.bz  $backup_dir/$(date +%F)-${f_name}.tar.bz
            rm -f ${f_name}.tar.bz
        done
        
        export ETCDCTL_API=3
        etcdctl --cert=/etc/kubernetes/pki/etcd/server.crt \
            --key=/etc/kubernetes/pki/etcd/server.key \
            --cacert=/etc/kubernetes/pki/etcd/ca.crt \
            snapshot save $backup_dir/$(date +%F)-k8s-snapshot.db
        cd $backup_dir
        tar -cjf $(date +%F)-k8s-snapshot.tar.bz $(date +%F)-k8s-snapshot.db 
        if [ $? -eq 0 ]; then
            file_size=$(du $(date +%F)-k8s-snapshot.tar.bz|awk '{print $1}')
            save_log "$file_size ${f_name}.tar.bz"
            save_log "finish tar ${f_name}.tar.bz"
        else
            file_size=0
            save_log "failed tar ${f_name}.tar.bz"
        fi
        rm -f $(date +%F)-k8s-snapshot.db
    }
    
    function rsync_backup_files () { 
        # 传输日志文件
        #传输到远程服务器备份, 需要配置免密ssh认证
        $ssh_command root@${BACK_SERVER} "mkdir -p ${BACK_SERVER_DIR}/${DATE}/"
        rsync -avz --bwlimit=5000 -e "${ssh_command}" $backup_dir/*.bz \
        root@${BACK_SERVER}:${BACK_SERVER_DIR}/${DATE}/
        [ $? -eq 0 ] && save_log "success rsync" || \
          save_log "failed rsync"
    }
    
    function delete_old_files () { 
        for delete_dir_keep_days in ${delete_dirs[@]}; do
            delete_dir=$(echo $delete_dir_keep_days|awk -F':' '{print $1}')
            keep_days=$(echo $delete_dir_keep_days|awk -F':' '{print $2}')
            [ -n "$delete_dir" ] && cd ${delete_dir}
            [ $? -eq 0 ] && find -L ${delete_dir} -mindepth 1 -mtime +$keep_days -exec rm -rf { } \;
        done
    }
    
    backup
    delete_old_files
    #rsync_backup_files
    
    save_log "finish $0\n"
    
    exit 0

## 5. etcd数据恢复 ##

> **注意**  
> 数据恢复操作，会停止全部应用状态和访问！！！

首先需要分别停掉三台Master机器的kube-apiserver，确保kube-apiserver已经停止了。

mv /etc/kubernetes/manifests /etc/kubernetes/manifests.bak
    docker ps|grep k8s_  # 查看etcd、api是否up，等待全部停止
    mv /var/lib/etcd /var/lib/etcd.bak

etcd集群用同一份snapshot恢复。

# 准备恢复文件
    cd /tmp
    tar -jxvf /data/backup/kubernetes/2018-09-18-k8s-snapshot.tar.bz
    rsync -avz 2018-09-18-k8s-snapshot.db 192.168.105.93:/tmp/
    rsync -avz 2018-09-18-k8s-snapshot.db 192.168.105.94:/tmp/

在lab1上执行：

cd /tmp/
    export ETCDCTL_API=3
    etcdctl snapshot restore 2018-09-18-k8s-snapshot.db \
        --endpoints=192.168.105.92:2379 \
        --name=lab1 \
        --cert=/etc/kubernetes/pki/etcd/server.crt \
        --key=/etc/kubernetes/pki/etcd/server.key \
        --cacert=/etc/kubernetes/pki/etcd/ca.crt \
        --initial-advertise-peer-urls=https://192.168.105.92:2380 \
        --initial-cluster-token=etcd-cluster-0 \
        --initial-cluster=lab1=https://192.168.105.92:2380,lab2=https://192.168.105.93:2380,lab3=https://192.168.105.94:2380 \
        --data-dir=/var/lib/etcd

在lab2上执行：

cd /tmp/
    export ETCDCTL_API=3
    etcdctl snapshot restore 2018-09-18-k8s-snapshot.db \
        --endpoints=192.168.105.93:2379 \
        --name=lab2 \
        --cert=/etc/kubernetes/pki/etcd/server.crt \
        --key=/etc/kubernetes/pki/etcd/server.key \
        --cacert=/etc/kubernetes/pki/etcd/ca.crt \
        --initial-advertise-peer-urls=https://192.168.105.93:2380 \
        --initial-cluster-token=etcd-cluster-0 \
        --initial-cluster=lab1=https://192.168.105.92:2380,lab2=https://192.168.105.93:2380,lab3=https://192.168.105.94:2380 \
        --data-dir=/var/lib/etcd

在lab3上执行：

cd /tmp/
    export ETCDCTL_API=3
    etcdctl snapshot restore 2018-09-18-k8s-snapshot.db \
        --endpoints=192.168.105.94:2379 \
        --name=lab3 \
        --cert=/etc/kubernetes/pki/etcd/server.crt \
        --key=/etc/kubernetes/pki/etcd/server.key \
        --cacert=/etc/kubernetes/pki/etcd/ca.crt \
        --initial-advertise-peer-urls=https://192.168.105.94:2380 \
        --initial-cluster-token=etcd-cluster-0 \
        --initial-cluster=lab1=https://192.168.105.92:2380,lab2=https://192.168.105.93:2380,lab3=https://192.168.105.94:2380 \
        --data-dir=/var/lib/etcd

全部恢复完成后，三台Master机器恢复manifests。

mv /etc/kubernetes/manifests.bak /etc/kubernetes/manifests

最后确认：

# 再次查看key
    [root@lab1 kubernetes]# etcdctl get / --prefix --keys-only --cert=/etc/kubernetes/pki/etcd/server.crt --key=/etc/kubernetes/pki/etcd/server.key --cacert=/etc/kubernetes/pki/etcd/ca.crt
    registry/apiextensions.k8s.io/customresourcedefinitions/apprepositories.kubeapps.com
    
    /registry/apiregistration.k8s.io/apiservices/v1.
    
    /registry/apiregistration.k8s.io/apiservices/v1.apps
    
    /registry/apiregistration.k8s.io/apiservices/v1.authentication.k8s.io
    
               ........此处省略..........
    [root@lab1 kubernetes]# kubectl get pod -n kube-system
    NAME                                              READY     STATUS    RESTARTS   AGE
    coredns-777d78ff6f-m5chm                          1/1       Running   1          18h
    coredns-777d78ff6f-xm7q8                          1/1       Running   1          18h
    dashboard-kubernetes-dashboard-7cfc6c7bf5-hr96q   1/1       Running   0          13h
    dashboard-kubernetes-dashboard-7cfc6c7bf5-x9p7j   1/1       Running   0          13h
    etcd-lab1                                         1/1       Running   0          18h
    etcd-lab2                                         1/1       Running   0          1m
    etcd-lab3                                         1/1       Running   0          18h
    kube-apiserver-lab1                               1/1       Running   0          18h
    kube-apiserver-lab2                               1/1       Running   0          1m
    kube-apiserver-lab3                               1/1       Running   0          18h
    kube-controller-manager-lab1                      1/1       Running   0          18h
    kube-controller-manager-lab2                      1/1       Running   0          1m
    kube-controller-manager-lab3                      1/1       Running   0          18h
    kube-flannel-ds-7w6rl                             1/1       Running   2          18h
    kube-flannel-ds-b9pkf                             1/1       Running   2          18h
    kube-flannel-ds-fck8t                             1/1       Running   1          18h
    kube-flannel-ds-kklxs                             1/1       Running   1          18h
    kube-flannel-ds-lxxx9                             1/1       Running   2          18h
    kube-flannel-ds-q7lpg                             1/1       Running   1          18h
    kube-flannel-ds-tlqqn                             1/1       Running   1          18h
    kube-proxy-85j7g                                  1/1       Running   1          18h
    kube-proxy-gdvkk                                  1/1       Running   1          18h
    kube-proxy-jw5gh                                  1/1       Running   1          18h
    kube-proxy-pgfxf                                  1/1       Running   1          18h
    kube-proxy-qx62g                                  1/1       Running   1          18h
    kube-proxy-rlbdb                                  1/1       Running   1          18h
    kube-proxy-whhcv                                  1/1       Running   1          18h
    kube-scheduler-lab1                               1/1       Running   0          18h
    kube-scheduler-lab2                               1/1       Running   0          1m
    kube-scheduler-lab3                               1/1       Running   0          18h
    kubernetes-dashboard-754f4d5f69-7npk5             1/1       Running   0          13h
    kubernetes-dashboard-754f4d5f69-whtg9             1/1       Running   0          13h
    tiller-deploy-98f7f7564-59hcs                     1/1       Running   0          13h

进相应的安装程序确认，数据全部正常。

## 6. 小结 ##

不管是二进制还是kubeadm安装的Kubernetes，其备份主要是通过etcd的备份完成的。而恢复时，主要考虑的是整个顺序：停止kube-apiserver，停止etcd，恢复数据，启动etcd，启动kube-apiserver。

参考资料：  
\[1\] [https://yq.aliyun.com/articles/561894][https_yq.aliyun.com_articles_561894]

[https_yq.aliyun.com_articles_561894]: https://yq.aliyun.com/articles/561894