安装etcd
安装包下载路径
https://download.csdn.net/download/wankwan/10902359
安装单节点etcd
vim conf.yml
name: etcd-1
data-dir: /opt/etcd-v3.3.10-linux-amd64/data
listen-client-urls: http://192.168.13.130:2379,http://127.0.0.1:2379
advertise-client-urls: http://192.168.13.130:2379,http://127.0.0.1:2379
listen-peer-urls: http://192.168.13.130:2380
initial-advertise-peer-urls: http://192.168.13.130:2380
initial-cluster: etcd-1=http://192.168.13.130:2380
initial-cluster-token: etcd-cluster-token
initial-cluster-state: new
启动etcd
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# ./etcd --config-file=conf.yml
2019-10-20 14:03:24.239088 I | etcdmain: Loading server configuration from "conf.yml"
2019-10-20 14:03:24.241164 I | etcdmain: etcd Version: 3.3.10
2019-10-20 14:03:24.241988 I | etcdmain: Git SHA: 27fc7e2
2019-10-20 14:03:24.242546 I | etcdmain: Go Version: go1.10.4
2019-10-20 14:03:24.243099 I | etcdmain: Go OS/Arch: linux/amd64
2019-10-20 14:03:24.243668 I | etcdmain: setting maximum number of CPUs to 1, total number of available CPUs is 1
2019-10-20 14:03:24.244295 N | etcdmain: the server is already initialized as member before, starting as etcd me mber...
2019-10-20 14:03:24.244873 I | embed: listening for peers on http://192.168.13.130:2380
2019-10-20 14:03:24.245519 I | embed: listening for client requests on 127.0.0.1:2379
2019-10-20 14:03:24.246034 I | embed: listening for client requests on 192.168.13.130:2379
2019-10-20 14:03:24.247124 I | etcdserver: name = etcd-1
2019-10-20 14:03:24.247591 I | etcdserver: data dir = /opt/etcd-v3.3.10-linux-amd64/data
2019-10-20 14:03:24.248013 I | etcdserver: member dir = /opt/etcd-v3.3.10-linux-amd64/data/member
2019-10-20 14:03:24.248388 I | etcdserver: heartbeat = 100ms
2019-10-20 14:03:24.248762 I | etcdserver: election = 1000ms
2019-10-20 14:03:24.249162 I | etcdserver: snapshot count = 100000
2019-10-20 14:03:24.249377 I | etcdserver: advertise client URLs = http://127.0.0.1:2379,http://192.168.13.130:2 379
2019-10-20 14:03:24.249704 I | etcdserver: restarting member e320d37d47ffd2b9 in cluster 5f9f57aff3a7b560 at com mit index 6
2019-10-20 14:03:24.250029 I | raft: e320d37d47ffd2b9 became follower at term 3
2019-10-20 14:03:24.250263 I | raft: newRaft e320d37d47ffd2b9 [peers: [], term: 3, commit: 6, applied: 0, lastin dex: 6, lastterm: 3]
2019-10-20 14:03:24.255862 W | auth: simple token is not cryptographically signed
2019-10-20 14:03:24.260080 I | etcdserver: starting server... [version: 3.3.10, cluster version: to_be_decided]
2019-10-20 14:03:24.264671 I | etcdserver/membership: added member e320d37d47ffd2b9 [http://192.168.13.130:2380] to cluster 5f9f57aff3a7b560
2019-10-20 14:03:24.267207 N | etcdserver/membership: set the initial cluster version to 3.3
2019-10-20 14:03:24.267878 I | etcdserver/api: enabled capabilities for version 3.3
2019-10-20 14:03:25.551322 I | raft: e320d37d47ffd2b9 is starting a new election at term 3
2019-10-20 14:03:25.551387 I | raft: e320d37d47ffd2b9 became candidate at term 4
2019-10-20 14:03:25.551469 I | raft: e320d37d47ffd2b9 received MsgVoteResp from e320d37d47ffd2b9 at term 4
2019-10-20 14:03:25.551507 I | raft: e320d37d47ffd2b9 became leader at term 4
2019-10-20 14:03:25.551524 I | raft: raft.node: e320d37d47ffd2b9 elected leader e320d37d47ffd2b9 at term 4
2019-10-20 14:03:25.554579 I | etcdserver: published {Name:etcd-1 ClientURLs:[http://127.0.0.1:2379 http://192.1 68.13.130:2379]} to cluster 5f9f57aff3a7b560
2019-10-20 14:03:25.556753 E | etcdmain: forgot to set Type=notify in systemd service file?
2019-10-20 14:03:25.557305 I | embed: ready to serve client requests
2019-10-20 14:03:25.561823 N | embed: serving insecure client requests on 127.0.0.1:2379, this is strongly disco uraged!
2019-10-20 14:03:25.564202 I | embed: ready to serve client requests
2019-10-20 14:03:25.568558 N | embed: serving insecure client requests on 192.168.13.130:2379, this is strongly discouraged!
查看节点信息
查看节点成员
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# etcdctl member list
e320d37d47ffd2b9, started, etcd-1, http://192.168.13.130:2380, http://127.0.0.1:2379,http://192.168.13.130:2379
查看集群状态（leader节点）
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# etcdctl --write-out=table endpoint status
+----------------+------------------+---------+---------+-----------+-----------+------------+
| ENDPOINT | ID | VERSION | DB SIZE | IS LEADER | RAFT TERM | RAFT INDEX |
+----------------+------------------+---------+---------+-----------+-----------+------------+
| 127.0.0.1:2379 | e320d37d47ffd2b9 | 3.3.10 | 20 kB | true | 4 | 13 |
+----------------+------------------+---------+---------+-----------+-----------+------------+
集群信息
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# etcdctl member list
e320d37d47ffd2b9, started, etcd-1, http://192.168.13.130:2380, http://127.0.0.1:2379,http://192.168.13.130:2379
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# curl http://127.0.0.1:2379/v2/stats/leader查看自己状态
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# curl http://127.0.0.1:2379/v2/stats/self
{"name":"etcd-1","id":"e320d37d47ffd2b9","state":"StateLeader","startTime":"2019-10-20T14:03:24.250394612+08:00","leaderInfo":{"leader":"e320d37d47ffd2b9","uptime":"7m45.794728901s","startTime":"2019-10-20T14:03:25.55155864+08:00"},"recvAppendRequestCnt":0,"sendAppendRequestCnt":0}root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64#
键值对写入读取
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# etcdctl put /aaa 111
OK
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# etcdctl get /aaa
/aaa
111
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# etcdctl put bbb 222
OK
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# etcdctl get bbb
bbb
222
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# etcdctl del bbb
1
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# etcdctl get bbb
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64#
查看全部key
过期时间(租约)
#生成租约定时器
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# etcdctl lease grant 50
lease 52b96de7d61a270f granted with TTL(50s)#关联租约到key
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# etcdctl put test_lease 50 --lease=52b96de7d61a270f
OK#查看key
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# etcdctl get test_lease
test_lease
50扫描二维码关注公众号，回复： 9404702 查看本文章
过期消失
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# etcdctl get test_lease
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64#
观察者
在第一个终端：
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# curl http://127.0.0.1:2379/v2/keys/foo?wait=true
然后在第二个终端去改变它的值
root@ubuntu-130:~# curl http://127.0.0.1:2379/v2/keys/foo -XPUT -d value=bar
{"action":"set","node":{"key":"/foo","value":"bar","modifiedIndex":7,"createdIndex":7}}
然后等待第一个终端的变化
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# curl http://127.0.0.1:2379/v2/keys/foo?wait=true
{"action":"set","node":{"key":"/foo","value":"bar","modifiedIndex":7,"createdIndex":7}}
分布式锁
在第一个终端
root@ubuntu-130:/opt/etcd-v3.3.10-linux-amd64# etcdctl lock my_mutex
my_mutex/52b96de7d61a271f
在第二个终端：
会等待进入，直到第一个终端的锁被释放
root@ubuntu-130:~# etcdctl lock my_mutex
javak客户端操作请参考github
