etcd迁移存储目录

背景：最近在Azure上自建原生k8s集群，然后很不稳定有时雪崩，日志一直报如下， 网上查了很多资料说是etcd数据存储磁盘io影响etcd查查询慢。确实我这块存储盘是hdd，于是打算迁到ssd盘试下还会不会有这种情况。

etcdserver: read-only range request took too long with etcd 3.2.24 #70082

 issue：https://github.com/kubernetes/kubernetes/issues/70082

迁移方法：

1. 关闭服务并拷贝数据库文件到新的目录下

[root@node1 ~]# systemctl stop etcd
[root@node1 ~]# cp -ar /data/etcd/ /var/lib/
[root@node1 ~]# ll /var/lib/etcd/
total 0
drwx------. 4 root root 29 Apr 28 05:54 member

　　2. 修改etcd.env文件新数据目录

[root@node1 ~]# vim /etc/etcd.env
# Environment file for etcd v3.3.12
ETCD_DATA_DIR=/var/lib/etcd

　　3.修改启动参数

[root@node1 ~]# vim /usr/local/bin/etcd
#!/bin/bash
/usr/bin/docker run 
  --restart=on-failure:5 
  --env-file=/etc/etcd.env 
  --net=host 
  -v /etc/ssl/certs:/etc/ssl/certs:ro 
  -v /etc/ssl/etcd/ssl:/etc/ssl/etcd/ssl:ro 
  -v /var/lib/etcd:/var/lib/etcd:rw 
  --memory=0 
  --blkio-weight=1000 
  --name=etcd1 
  quay.io/coreos/etcd:v3.3.12 
  /usr/local/bin/etcd 
  "$@"

　　4.启动服务

[root@node1 ~]# systemctl start etcd
[root@node1 ~]# systemctl status etcd
● etcd.service - etcd docker wrapper
   Loaded: loaded (/etc/systemd/system/etcd.service; enabled; vendor preset: disabled)
   Active: active (running) since Wed 2020-04-29 12:40:24 UTC; 5s ago
  Process: 4218 ExecStop=/usr/bin/docker stop etcd1 (code=exited, status=0/SUCCESS)
  Process: 6071 ExecStartPre=/usr/bin/docker rm -f etcd1 (code=exited, status=0/SUCCESS)
 Main PID: 6086 (etcd)
    Tasks: 16
   Memory: 34.4M
   CGroup: /system.slice/etcd.service
           ├─6086 /bin/bash /usr/local/bin/etcd
           └─6088 /usr/bin/docker run --restart=on-failure:5 --env-file=/etc/etcd.env --net=host -v /etc/ssl/certs:/etc/ssl/certs:ro -v /etc/ssl/etcd/ssl:/etc/ssl/etcd/ssl:ro -v /var...

Apr 29 12:40:24 node1 etcd[6086]: 2020-04-29 12:40:24.938238 I | rafthttp: established a TCP streaming connection with peer 1c74700fc9501a08 (stream Message reader)
Apr 29 12:40:24 node1 etcd[6086]: 2020-04-29 12:40:24.938385 I | rafthttp: established a TCP streaming connection with peer bfb5d71282c2db49 (stream MsgApp v2 reader)
Apr 29 12:40:24 node1 etcd[6086]: 2020-04-29 12:40:24.979248 I | etcdserver: 465aba9a8e04dd3f initialzed peer connection; fast-forwarding 3 ticks (election ticks 5) with...ctive peer(s)
Apr 29 12:40:25 node1 etcd[6086]: 2020-04-29 12:40:25.006641 I | mvcc: store.index: compact 1078020
Apr 29 12:40:25 node1 etcd[6086]: 2020-04-29 12:40:25.010060 I | mvcc: finished scheduled compaction at 1078020 (took 2.330859ms)
Apr 29 12:40:25 node1 etcd[6086]: 2020-04-29 12:40:25.016608 I | etcdserver: published {Name:etcd1 ClientURLs:[https://10.10.10.11:2379]} to cluster 4059f5ad1e3ba1cc
Apr 29 12:40:25 node1 etcd[6086]: 2020-04-29 12:40:25.016643 I | embed: ready to serve client requests
Apr 29 12:40:25 node1 etcd[6086]: 2020-04-29 12:40:25.016964 I | embed: ready to serve client requests
Apr 29 12:40:25 node1 etcd[6086]: 2020-04-29 12:40:25.019571 I | embed: serving client requests on 10.10.10.11:2379
Apr 29 12:40:25 node1 etcd[6086]: 2020-04-29 12:40:25.020805 I | embed: serving client requests on 127.0.0.1:2379
Hint: Some lines were ellipsized, use -l to show in full.
[root@node1 ~]# kubectl get cs
NAME                 STATUS    MESSAGE             ERROR
scheduler            Healthy   ok
controller-manager   Healthy   ok
etcd-0               Healthy   {"health":"true"}
etcd-1               Healthy   {"health":"true"}
etcd-2               Healthy   {"health":"true"}