etcd 分布式集群搭建和使用
目录
- 1.多节点服务集群搭建
- 启动节点1
- 启动节点2
- 启动节点3
- 2.使用
- 查看节点信息
- 集群状态
- 键值对 读写
- 分布式锁
- 3.参考
上篇文章etcd 入门 中已经介绍了etcd基本功能，单节点服务的安装和使用。
本文将介绍etcd 分布式多节点的安装、配置和使用。
由于资源限制，本文以单机多节点服务为例进行阐述。
在实际应用场景中，为了高可用和容灾，是需要多机器安装的。
1.多节点服务集群搭建
操作系统使用的 centos 6.8。
默认情况下，端口2379用于提供HTTP API服务，端口2380用于节点间通信。
在单机情况下，多节点服务需要使用不同端口。
三节点集群信息如下：
| name | ip | port |
|---|---|---|
| etcd-01 | 127.0.0.1 | 2379,2380 |
| etcd-02 | 127.0.0.1 | 2479,2480 |
| etcd-03 | 127.0.0.1 | 2579,2580 |
启动节点1
定义启动脚本start_etcd1.sh
TOKEN=token-01CLUSTER_STATE=newNAME_1=etcd-01NAME_2=etcd-02NAME_3=etcd-03HOST_1=127.0.0.1HOST_2=127.0.0.1HOST_3=127.0.0.1PORT_API_1=2379PORT_PEER_1=2380PORT_API_2=2479PORT_PEER_2=2480PORT_API_3=2579PORT_PEER_3=2580CLUSTER=${NAME_1}=http://${HOST_1}:${PORT_PEER_1},${NAME_2}=http://${HOST_2}:${PORT_PEER_2},${NAME_3}=http://${HOST_3}:${PORT_PEER_3}# For every machineTHIS_NAME=${NAME_1}THIS_IP=${HOST_1}THIS_PORT_API=${PORT_API_1}THIS_PORT_PEER=${PORT_PEER_1}./etcd --data-dir=data.${THIS_NAME} --name ${THIS_NAME} \--initial-advertise-peer-urls http://${THIS_IP}:${THIS_PORT_PEER} --listen-peer-urls http://${THIS_IP}:${THIS_PORT_PEER} \--advertise-client-urls http://${THIS_IP}:${THIS_PORT_API} --listen-client-urls http://${THIS_IP}:${THIS_PORT_API} \--initial-cluster ${CLUSTER} \--initial-cluster-state ${CLUSTER_STATE} --initial-cluster-token ${TOKEN}
启动
bash start_etcd2.sh
启动节点2
定义启动脚本start_etcd2.sh,
只需将启动脚本start_etcd1.sh中的配置项修改：
THIS_NAME=${NAME_2}THIS_IP=${HOST_2}THIS_PORT_API=${PORT_API_2}THIS_PORT_PEER=${PORT_PEER_2}
启动
bash start_etcd2.sh
启动节点3
定义启动脚本start_etcd3.sh，
只需将启动脚本start_etcd1.sh中的配置项修改：
THIS_NAME=${NAME_3}THIS_IP=${HOST_3}THIS_PORT_API=${PORT_API_3}THIS_PORT_PEER=${PORT_PEER_3}
启动
bash start_etcd3.sh
2.使用
查看节点信息
export ETCDCTL_API=3HOST_1=127.0.0.1HOST_2=127.0.0.1HOST_3=127.0.0.1PORT_API_1=2379PORT_API_2=2479PORT_API_3=2579ENDPOINTS=$HOST_1:${PORT_API_1},$HOST_2:${PORT_API_2},$HOST_3:${PORT_API_3}./etcdctl --endpoints=$ENDPOINTS member list$ ./etcdctl --endpoints=$ENDPOINTS member list264ae6bc59e99892, started, etcd-01, http://127.0.0.1:2380, http://127.0.0.1:2379, falsedbafe5ad6b652eda, started, etcd-02, http://127.0.0.1:2480, http://127.0.0.1:2479, falsef570ae41f524bdcb, started, etcd-03, http://127.0.0.1:2580, http://127.0.0.1:2579, false
或者
$ ./etcdctl --endpoints=$ENDPOINTS --write-out=table member list+------------------+---------+---------+-----------------------+-----------------------+------------+| ID | STATUS | NAME | PEER ADDRS | CLIENT ADDRS | IS LEARNER |+------------------+---------+---------+-----------------------+-----------------------+------------+| 264ae6bc59e99892 | started | etcd-01 | http://127.0.0.1:2380 | http://127.0.0.1:2379 | false || dbafe5ad6b652eda | started | etcd-02 | http://127.0.0.1:2480 | http://127.0.0.1:2479 | false || f570ae41f524bdcb | started | etcd-03 | http://127.0.0.1:2580 | http://127.0.0.1:2579 | false |
集群状态
$ ./etcdctl --endpoints=$ENDPOINTS endpoint status127.0.0.1:2379, 264ae6bc59e99892, 3.4.13, 20 kB, false, false, 8, 10, 10,127.0.0.1:2479, dbafe5ad6b652eda, 3.4.13, 33 kB, true, false, 8, 10, 10,127.0.0.1:2579, f570ae41f524bdcb, 3.4.13, 20 kB, false, false, 8, 10, 10,$ ./etcdctl --endpoints=$ENDPOINTS --write-out=table endpoint status+----------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+| ENDPOINT | ID | VERSION | DB SIZE | IS LEADER | IS LEARNER | RAFT TERM | RAFT INDEX | RAFT APPLIED INDEX | ERRORS |+----------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+| 127.0.0.1:2379 | 264ae6bc59e99892 | 3.4.13 | 20 kB | false | false | 8 | 10 | 10 | || 127.0.0.1:2479 | dbafe5ad6b652eda | 3.4.13 | 33 kB | true | false | 8 | 10 | 10 | || 127.0.0.1:2579 | f570ae41f524bdcb | 3.4.13 | 20 kB | false | false | 8 | 10 | 10 | |+----------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+
可以看到，127.0.0.1:2479 这个节点是leader。
查看节点健康状况
$ ./etcdctl --endpoints=$ENDPOINTS endpoint health127.0.0.1:2379 is healthy: successfully committed proposal: took = 5.843376ms127.0.0.1:2479 is healthy: successfully committed proposal: took = 4.92724ms127.0.0.1:2579 is healthy: successfully committed proposal: took = 7.661623ms$ ./etcdctl --endpoints=$ENDPOINTS --write-out=table endpoint health+----------------+--------+------------+-------+| ENDPOINT | HEALTH | TOOK | ERROR |+----------------+--------+------------+-------+| 127.0.0.1:2379 | true | 8.470348ms | || 127.0.0.1:2479 | true | 4.540441ms | || 127.0.0.1:2579 | true | 8.666543ms | |+----------------+--------+------------+-------+
键值对 读写
$ ./etcdctl --endpoints=$ENDPOINTS put foo "Hello World"OK$ ./etcdctl --endpoints=$ENDPOINTS get foofooHello World
分布式锁
在终端1中获取锁
$ ./etcdctl --endpoints=$ENDPOINTS lock mutex1mutex1/3dcb7516bf48a904
在终端2中获取同一把锁，会被卡住
$ ./etcdctl --endpoints=$ENDPOINTS lock mutex1
此时，停止终端1的操作，释放锁，终端2才可以获取到锁:
$ ./etcdctl --endpoints=$ENDPOINTS lock mutex1mutex1/3dcb7516bf48a907
3.参考
github etcd 官方文档
野性酷女
以你之姓@
分手后的思念是犯贱
我就是我
还没有评论，来说两句吧...