zookeeper相关操作

zookeeper相关命令

zk服务器端命令

命令	功能
zkServer.sh start	启动zookeeper
zkServer.sh stop	关闭zookeeper
zkServer.sh restart	重启zookeeper
zkServer.sh status	查看zookeeper服务状态
zkCli.sh [-server] [ip:port]	启动zookeeper客户端

zk客户端命令

命令	功能
help	显示所有操作命令
ls path	查看当前znode子结点
ls2 path	查看当前znode子结点并显示znode元数据
create [-s] [-e] path data	创建znode，并添加数据 -s：序列节点 -e：临时节点
get path	获得znode的值
set	重新设置znode的值
stat	查看znode状态
delete	删除znode
rmr	递归删除znode
quit	退出客户端

znode操作

普通结点

[root@zk01 zookeeper]# zkCli.sh -server zk02:2181

[zk: zk02:2181(CONNECTED) 5] ls /
[zookeeper]
[zk: zk02:2181(CONNECTED) 6] create /a "abc"
Created /a
[zk: zk02:2181(CONNECTED) 7] get /a
abc

临时结点

[zk: zk02:2181(CONNECTED) 8] create -e /b 'bcd'
Created /b
[zk: zk02:2181(CONNECTED) 9] ls /
[a, b, zookeeper]

退出客户端
[zk: zk02:2181(CONNECTED) 10] quit

WATCHER::
WatchedEvent state:Closed type:None path:null
2021-03-06 21:12:34,506 [myid:] - INFO  [main:ZooKeeper@1422] - Session: 0x200002280f00000 closed
2021-03-06 21:12:34,506 [myid:] - INFO  [main-EventThread:ClientCnxn$EventThread@524] - EventThread shut down for session: 0x200002280f00000

重新连接客户端查看结点

[root@zk01 zookeeper]# zkCli.sh -server zk02:2181

[zk: zk02:2181(CONNECTED) 0] ls /
[a, zookeeper]

序列结点

[zk: zk02:2181(CONNECTED) 0] ls /
[a, zookeeper]
[zk: zk02:2181(CONNECTED) 1] create -s /c 'abc'
Created /c0000000003
[zk: zk02:2181(CONNECTED) 2] ls /
[a, c0000000003, zookeeper]
[zk: zk02:2181(CONNECTED) 3] create -s /c 'abc'
Created /c0000000004

[zk: zk02:2181(CONNECTED) 8] ls /
[a, c0000000003, c0000000004, zookeeper]

[zk: zk02:2181(CONNECTED) 10] get /c0000000004
abc

查看zookeeper的事务日志

在ZooKeeper集群启动后，当第一个客户端连接到某个服务器节点时，会创建一个会话，这个会话也是事务，于是创建第一个事务日志，一般名为log.100000001，这里的100000001是这次会话的事务id(zxid)。之后的事务都将写入到这个文件中，直到拍下一个快照。

[root@zk02 zookeeper]# ll zk*/*
-rw-r--r-- 1 root root  2 Mar  6 22:51 zkSnapshot/myid
-rw-r--r-- 1 root root  4 Mar  6 22:52 zkSnapshot/zookeeper_server.pid
-rw-r--r-- 1 root root  2 Mar  6 22:50 zkTxData/myid

zkSnapshot/version-2:
total 12
-rw-r--r-- 1 root root   1 Mar  6 22:52 acceptedEpoch
-rw-r--r-- 1 root root   1 Mar  6 22:52 currentEpoch
-rw-r--r-- 1 root root 541 Mar  6 22:52 snapshot.0

客户端连接zookeeper后查看

[root@zk02 zookeeper]# ll zk*/*
-rw-r--r-- 1 root root  2 Mar  6 22:51 zkSnapshot/myid
-rw-r--r-- 1 root root  4 Mar  6 22:52 zkSnapshot/zookeeper_server.pid
-rw-r--r-- 1 root root  2 Mar  6 22:50 zkTxData/myid

zkSnapshot/version-2:
total 12
-rw-r--r-- 1 root root   1 Mar  6 22:52 acceptedEpoch
-rw-r--r-- 1 root root   1 Mar  6 22:52 currentEpoch
-rw-r--r-- 1 root root 541 Mar  6 22:52 snapshot.0

zkTxData/version-2:
total 8
-rw-r--r-- 1 root root 67108880 Mar  6 23:07 log.100000001

如果是事务ZXID5触发的拍快照，那么快照名就是snapshot.ZXID5，拍完后，下一个事务的ID就是ZXID6，于是新的事务日志名为log.ZXID6。

[root@zk03 zookeeper]# java -cp /opt/module/zookeeper/lib/zookeeper-3.5.5.jar:/opt/module/zookeeper/lib/slf4j-api-1.7.25.jar:/opt/module/zookeeper/lib/zookeeper-jute-3.5.5.jar org.apache.zookeeper.server.LogFormatter /opt/module/zookeeper/zkTxData/version-2/log.100000001 
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
ZooKeeper Transactional Log File with dbid 0 txnlog format version 2
3/6/21 11:07:22 PM EST session 0x200008a6df70000 cxid 0x0 zxid 0x100000001 createSession 30000

3/6/21 11:09:41 PM EST session 0x200008a6df70000 cxid 0x2 zxid 0x100000002 create '/a,,v{s{31,s{'world,'anyone}}},F,1

3/6/21 11:09:48 PM EST session 0x2
00008a6df70000 cxid 0x3 zxid 0x100000003 create '/b,,v{s{31,s{'world,'anyone}}},F,2

3/6/21 11:10:04 PM EST session 0x200008a6df70000 cxid 0x4 zxid 0x100000004 closeSession null
3/6/21 11:10:13 PM EST session 0x200008a6df70001 cxid 0x0 zxid 0x100000005 createSession 30000

EOF reached after 5 txns.