CentOS下安裝etcd集群

一 . 在所有機器上安裝etcd

我們准備3台機器 

172.18.0.231	集群節點1
172.18.0.232	集群節點2
172.18.0.233	集群節點3

 

 

 

 

#yum安裝etcd
yum install -y etcd

 

二 . 修改配置

#備份原配置文件並編輯
cp /etc/etcd/etcd.conf /etc/etcd/etcd.conf.bk
vim /etc/etcd/etcd.conf

 

參考配置:

Node1 : 172.18.0.231

#[Member]
ETCD_DATA_DIR="/var/lib/etcd/etcd231"
ETCD_WAL_DIR="/var/lib/etcd/etcd231/wal"
ETCD_LISTEN_PEER_URLS="http://172.18.0.231:2380"
ETCD_LISTEN_CLIENT_URLS="http://172.18.0.231:2379,http://127.0.0.1:2379"
ETCD_NAME="etcd231"
#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="http://172.18.0.231:2380"
ETCD_ADVERTISE_CLIENT_URLS="http://172.18.0.231:2379,http://127.0.0.1:2379"
ETCD_INITIAL_CLUSTER="etcd231=http://172.18.0.231:2380,etcd232=http://172.18.0.232:2380,etcd233=http://172.18.0.233:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster-wanma"
ETCD_INITIAL_CLUSTER_STATE="new"

 

Node2 : 172.18.0.232

#[Member]
ETCD_DATA_DIR="/var/lib/etcd/etcd232"
ETCD_WAL_DIR="/var/lib/etcd/etcd232/wal"
ETCD_LISTEN_PEER_URLS="http://172.18.0.232:2380"
ETCD_LISTEN_CLIENT_URLS="http://172.18.0.232:2379,http://127.0.0.1:2379"
ETCD_NAME="etcd232"
#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="http://172.18.0.232:2380"
ETCD_ADVERTISE_CLIENT_URLS="http://172.18.0.232:2379,http://127.0.0.1:2379"
ETCD_INITIAL_CLUSTER="etcd231=http://172.18.0.231:2380,etcd232=http://172.18.0.232:2380,etcd233=http://172.18.0.233:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster-wanma"
ETCD_INITIAL_CLUSTER_STATE="new"

 

Node3 : 172.18.0.233

#[Member]
ETCD_DATA_DIR="/var/lib/etcd/etcd233"
ETCD_WAL_DIR="/var/lib/etcd/etcd233/wal"
ETCD_LISTEN_PEER_URLS="http://172.18.0.233:2380"
ETCD_LISTEN_CLIENT_URLS="http://172.18.0.233:2379,http://127.0.0.1:2379"
ETCD_NAME="etcd233"
#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="http://172.18.0.233:2380"
ETCD_ADVERTISE_CLIENT_URLS="http://172.18.0.233:2379,http://127.0.0.1:2379"
ETCD_INITIAL_CLUSTER="etcd231=http://172.18.0.231:2380,etcd232=http://172.18.0.232:2380,etcd233=http://172.18.0.233:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster-wanma"
ETCD_INITIAL_CLUSTER_STATE="new"

 

三 . 啟動集群

#啟動etcd服務
systemctl restart etcd

#設定etcd服務為開機自啟動
systemctl enable etcd

注意 , 第一台啟動的etcd(master節點)(isLeader=true)會等待第二台啟動之后 ,才會啟動成功

 

四.集群新增額外節點(臨時節點)

步驟1 : 加入成員

#增加一個集群節點 , 首先新節點需要配置並啟動etcd
etcdctl member add name=etcd234 --peer-urls="http://172.18.0.234:2380"

步驟2 : 刪除新節點的data目錄

rm -rf /var/lib/etcd/etcd234/*

步驟3 : 新節點增加配置etcd.conf

注意 , 里面的 ETCD_INITIAL_CLUSTER_STATE="existing" 代表已存在節點

步驟4 : 啟動新節點的etcd服務

systemctl start etcd

 

PS : 步驟不能錯 , 所以如果有可能 , 請新加節點之后 , 集群重啟一下 , 比較不容易錯

 

 

五 . 常用命令

#查看集群健康狀態
etcdctl cluster-health

#查看集群所有節點
etcdctl member list

#把一台設備移除出集群 , 后面是集群節點號 , 使用list可以查看到
#移除之后,該節點的etcd服務自動關閉
etcdctl member remove 1e82894832618580

#更新一個節點
etcdctl member update 1e82894832618580

#設置key=hello , value=world
etcdctl set  hello world

#查看key的值
etcdctl get hello