Zookeeper系列一：Zookeeper基礎命令操做

時間  2021-01-27
標籤 java node mysql git github 面試 spring sql shell apache 欄目 Zookeeper 简体版
原文   原文鏈接

有些事不是努力就能夠改變的，五十塊的人民幣設計的再好看，也沒有一百塊的招人喜歡。java

https://raw.githubusercontent.com/longfeizheng/longfeizheng.github.io/master/images/spring-security-OAuth209.png

前言

因爲公司年末要更換辦公地點，因此最近投了一下簡歷，發現面試官如今很喜歡問dubbo、zookeeper和高併發等。因爲公司沒有使用dubbo，只知道dubbo是一個遠程服務調用的分佈式框架，zookeeper爲分佈式應用程序協調服務。所以，本週查閱資料整理下zookeeper學習筆記。node

安裝zookeeper

安裝參考連接http://www.javashuo.com/article/p-wbhetwvn-mx.htmlmysql

基礎命令操做

啓動zk服務

  • ./zkServer.sh start
[root@localhost bin]# ./zkServer.sh
ZooKeeper JMX enabled by default
Using config: /usr/home/zookeeper-3.4.11/bin/../conf/zoo.cfg
Usage: ./zkServer.sh {start|start-foreground|stop|restart|status|upgrade|print-cmd}
# 提示要以./zkCli.sh start 啓動zk
./zkCli.sh start

查看zk的運行狀態

  • ./zkServer.sh status 因爲我已經配置了zk的集羣，因此此處顯示狀態爲leader
[root@localhost bin]# ./zkServer.sh status
ZooKeeper JMX enabled by default
Using config: /usr/home/zookeeper-3.4.11/bin/../conf/zoo.cfg
Mode: leader

客戶端連接zk

[root@localhost bin]# ./zkCli.sh 
......
WatchedEvent state:SyncConnected type:None path:null
[zk: localhost:2181(CONNECTED) 0]

help 查看客戶端幫助命令

  • help
[zk: localhost:2181(CONNECTED) 0] help
ZooKeeper -server host:port cmd args
	stat path [watch]
	set path data [version]
	ls path [watch]
	delquota [-n|-b] path
	ls2 path [watch]
	setAcl path acl
	setquota -n|-b val path
	history 
	redo cmdno
	printwatches on|off
	delete path [version]
	sync path
	listquota path
	rmr path
	get path [watch]
	create [-s] [-e] path data acl
	addauth scheme auth
	quit 
	getAcl path
	close 
	connect host:port
[zk: localhost:2181(CONNECTED) 1]

ls 查看

  • ls 查看命令(niocoder是我測試集羣建立的節點，默認只有zookeeper一個節點)
[zk: localhost:2181(CONNECTED) 1] ls /
[niocoder, zookeeper]
[zk: localhost:2181(CONNECTED) 2] ls /zookeeper 
[quota]
[zk: localhost:2181(CONNECTED) 4] ls /zookeeper/quota
[]

get 獲取節點數據和更新信息

  • get內容爲空
  • cZxid ：建立節點的id
  • ctime ： 節點的建立時間
  • mZxid ：修改節點的id
  • mtime ：修改節點的時間
  • pZxid ：子節點的id
  • cversion : 子節點的版本
  • dataVersion ： 當前節點數據的版本
  • aclVersion ：權限的版本
  • ephemeralOwner ：判斷是不是臨時節點
  • dataLength ： 數據的長度
  • numChildren ：子節點的數量
[zk: localhost:2181(CONNECTED) 7] get /zookeeper #下面空行說明節點內容爲空

cZxid = 0x0
ctime = Thu Jan 01 00:00:00 UTC 1970
mZxid = 0x0
mtime = Thu Jan 01 00:00:00 UTC 1970
pZxid = 0x0
cversion = -1
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 0
numChildren = 1
[zk: localhost:2181(CONNECTED) 8]

stat 得到節點的更新信息

  • stat
[zk: localhost:2181(CONNECTED) 8] stat /zookeeper
cZxid = 0x0
ctime = Thu Jan 01 00:00:00 UTC 1970
mZxid = 0x0
mtime = Thu Jan 01 00:00:00 UTC 1970
pZxid = 0x0
cversion = -1
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 0
numChildren = 1

ls2 ls命令和stat命令的整合

  • ls2
[zk: localhost:2181(CONNECTED) 10] ls2 /zookeeper
[quota]
cZxid = 0x0
ctime = Thu Jan 01 00:00:00 UTC 1970
mZxid = 0x0
mtime = Thu Jan 01 00:00:00 UTC 1970
pZxid = 0x0
cversion = -1
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 0
numChildren = 1
[zk: localhost:2181(CONNECTED) 11]

create 建立節點

  • create [-s] [-e] path data acl 能夠注意一下各個版本的變化
#建立merryyou節點，節點的內容爲merryyou
[zk: localhost:2181(CONNECTED) 1] create /merryyou merryyou
Created /merryyou
#得到merryyou節點內容
[zk: localhost:2181(CONNECTED) 3] get /merryyou
merryyou
cZxid = 0x200000004
ctime = Sat Jun 02 14:20:06 UTC 2018
mZxid = 0x200000004
mtime = Sat Jun 02 14:20:06 UTC 2018
pZxid = 0x200000004
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 8
numChildren = 0

create -e 建立臨時節點

  • create -e
#建立臨時節點
[zk: localhost:2181(CONNECTED) 4] create -e  /merryyou/temp merryyou
Created /merryyou/temp
[zk: localhost:2181(CONNECTED) 5] get /merryyou
merryyou
cZxid = 0x200000004
ctime = Sat Jun 02 14:20:06 UTC 2018
mZxid = 0x200000004
mtime = Sat Jun 02 14:20:06 UTC 2018
pZxid = 0x200000005
cversion = 1
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 8
numChildren = 1
[zk: localhost:2181(CONNECTED) 6] get /merryyou/temp
merryyou
cZxid = 0x200000005
ctime = Sat Jun 02 14:22:24 UTC 2018
mZxid = 0x200000005
mtime = Sat Jun 02 14:22:24 UTC 2018
pZxid = 0x200000005
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x2000000d4500000
dataLength = 8
numChildren = 0
[zk: localhost:2181(CONNECTED) 7] 
#斷開重連以後，臨時節點自動消失
WATCHER::

WatchedEvent state:SyncConnected type:None path:null
#由於默認的心跳機制，此時查詢臨時節點還存在
[zk: localhost:2181(CONNECTED) 0] ls /merryyou
[temp]
#再次查詢，臨時節點消失
[zk: localhost:2181(CONNECTED) 1] ls /merryyou
[]
[zk: localhost:2181(CONNECTED) 2]

create -s 建立順序節點 自動累加

  • create -s
# 建立順序節點，順序節點會自動累加
[zk: localhost:2181(CONNECTED) 2] create -s /merryyou/sec seq
Created /merryyou/sec0000000001
[zk: localhost:2181(CONNECTED) 3] create -s /merryyou/sec seq
Created /merryyou/sec0000000002

set path data [version] 修改節點

[zk: localhost:2181(CONNECTED) 6] get /merryyou
merryyou
cZxid = 0x200000004
ctime = Sat Jun 02 14:20:06 UTC 2018
mZxid = 0x200000004
mtime = Sat Jun 02 14:20:06 UTC 2018
pZxid = 0x200000009
cversion = 4
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 8
numChildren = 2
# 修改節點內容爲new-merryyou
[zk: localhost:2181(CONNECTED) 7] set /merryyou new-merryyou
cZxid = 0x200000004
ctime = Sat Jun 02 14:20:06 UTC 2018
mZxid = 0x20000000a
mtime = Sat Jun 02 14:29:23 UTC 2018
pZxid = 0x200000009
cversion = 4
dataVersion = 1
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 12
numChildren = 2
#再次查詢，節點內容已經修改
[zk: localhost:2181(CONNECTED) 8] get /merryyou
new-merryyou
cZxid = 0x200000004
ctime = Sat Jun 02 14:20:06 UTC 2018
mZxid = 0x20000000a
mtime = Sat Jun 02 14:29:23 UTC 2018
pZxid = 0x200000009
cversion = 4
dataVersion = 1
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 12
numChildren = 2
#set 根據版本號更新 dataVersion 樂觀鎖
[zk: localhost:2181(CONNECTED) 9] set /merryyou test-merryyou 1
cZxid = 0x200000004
ctime = Sat Jun 02 14:20:06 UTC 2018
mZxid = 0x20000000b
mtime = Sat Jun 02 14:31:30 UTC 2018
pZxid = 0x200000009
cversion = 4
dataVersion = 2
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 13
numChildren = 2
#由於數據的版本號已經修改成2 再次使用版本號1修改節點提交錯誤
[zk: localhost:2181(CONNECTED) 10] set /merryyou test-merryyou 1
version No is not valid : /merryyou

delete path [version] 刪除節點

[zk: localhost:2181(CONNECTED) 13] delete /merryyou/sec000000000

sec0000000001   sec0000000002
[zk: localhost:2181(CONNECTED) 13] delete /merryyou/sec0000000001
[zk: localhost:2181(CONNECTED) 14] ls /merryyou
[sec0000000002]
[zk: localhost:2181(CONNECTED) 15] 
#版本號操做與set相似 version

watcher通知機制

關於watcher機制大致的理解能夠爲，當每一個節點發生變化，都會觸發watcher事件，相似於mysql的觸發器。zk中 watcher是一次性的，觸發後當即銷燬。能夠參考http://www.javashuo.com/article/p-wuvkttpg-cp.htmlgit

  • stat path [watch] 設置watch事件
  • get path [watch] 設置watch事件
  • 子節點建立和刪除時觸發watch事件，子節點修改不會觸發該事件
stat path [watch] 設置watch事件
#添加watch 事件
[zk: localhost:2181(CONNECTED) 18] stat /longfei watch
Node does not exist: /longfei
#建立longfei節點時觸發watcher事件
[zk: localhost:2181(CONNECTED) 19] create /longfei test

WATCHER::

WatchedEvent state:SyncConnected type:NodeCreated path:/longfei
Created /longfei
get path [watch] 設置watch事件
#使用get命令添加watch事件
[zk: localhost:2181(CONNECTED) 20] get /longfei watch
test
cZxid = 0x20000000e
ctime = Sat Jun 02 14:43:15 UTC 2018
mZxid = 0x20000000e
mtime = Sat Jun 02 14:43:15 UTC 2018
pZxid = 0x20000000e
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 4
numChildren = 0
#修改節點觸發watcher事件
[zk: localhost:2181(CONNECTED) 21] set /longfei new_test

WATCHER::

WatchedEvent state:SyncConnected type:NodeDataChanged path:/longfei
cZxid = 0x20000000e
ctime = Sat Jun 02 14:43:15 UTC 2018
mZxid = 0x20000000f
mtime = Sat Jun 02 14:45:06 UTC 2018
pZxid = 0x20000000e
cversion = 0
dataVersion = 1
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 8
numChildren = 0
[zk: localhost:2181(CONNECTED) 22] 
#刪除觸發watcher事件
[zk: localhost:2181(CONNECTED) 23] get /longfei watch
new_test
cZxid = 0x20000000e
ctime = Sat Jun 02 14:43:15 UTC 2018
mZxid = 0x20000000f
mtime = Sat Jun 02 14:45:06 UTC 2018
pZxid = 0x20000000e
cversion = 0
dataVersion = 1
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 8
numChildren = 0
[zk: localhost:2181(CONNECTED) 24] delete /longfei

WATCHER::

WatchedEvent state:SyncConnected type:NodeDeleted path:/longfei
[zk: localhost:2181(CONNECTED) 25]

ACL權限控制

ZK的節點有5種操做權限：CREATE、READ、WRITE、DELETE、ADMIN 也就是 增、刪、改、查、管理權限，這5種權限簡寫爲crwda(即：每一個單詞的首字符縮寫)。 注：這5種權限中，delete是指對子節點的刪除權限，其它4種權限指對自身節點的操做權限github

身份的認證有4種方式：面試

  • world：默認方式，至關於全世界都能訪問
  • auth：表明已經認證經過的用戶(cli中能夠經過addauth digest user:pwd 來添加當前上下文中的受權用戶)
  • digest：即用戶名:密碼這種方式認證，這也是業務系統中最經常使用的
  • ip：使用Ip地址認證

使用[scheme:id:permissions]來表示acl權限spring

getAcl:獲取某個節點的acl權限信息
#獲取節點權限信息默認爲 world:cdrwa任何人均可以訪問
[zk: localhost:2181(CONNECTED) 34] getAcl /merryyou
'world,'anyone
: cdrwa
[zk: localhost:2181(CONNECTED) 35]
setAcl 設置權限
[zk: localhost:2181(CONNECTED) 35] create /merryyou/test test
Created /merryyou/test
[zk: localhost:2181(CONNECTED) 36] getAcl /merryyou/test
'world,'anyone
: cdrwa
#設置節點權限 crwa 不容許刪除
[zk: localhost:2181(CONNECTED) 37] setAcl /merryyou/test world:anyone:crwa
cZxid = 0x200000018
ctime = Sat Jun 02 16:18:18 UTC 2018
mZxid = 0x200000018
mtime = Sat Jun 02 16:18:18 UTC 2018
pZxid = 0x200000018
cversion = 0
dataVersion = 0
aclVersion = 1
ephemeralOwner = 0x0
dataLength = 4
numChildren = 0
#查詢剛纔設置的acl權限信息 crwa 沒有刪除權限
[zk: localhost:2181(CONNECTED) 38] getAcl /merryyou/test
'world,'anyone
: crwa
[zk: localhost:2181(CONNECTED) 39] 
[zk: localhost:2181(CONNECTED) 39] create /merryyou/test/abc abc
Created /merryyou/test/abc
#刪除子節點的時候提交權限不足
[zk: localhost:2181(CONNECTED) 40] delete /merryyou/test/abc
Authentication is not valid : /merryyou/test/abc
#設置節點的權限信息爲rda
[zk: localhost:2181(CONNECTED) 41] setAcl /merryyou/test world:anyone:rda 
cZxid = 0x200000018
ctime = Sat Jun 02 16:18:18 UTC 2018
mZxid = 0x200000018
mtime = Sat Jun 02 16:18:18 UTC 2018
pZxid = 0x20000001a
cversion = 1
dataVersion = 0
aclVersion = 2
ephemeralOwner = 0x0
dataLength = 4
numChildren = 1
[zk: localhost:2181(CONNECTED) 42] getAcl /merryyou/test
'world,'anyone
: dra
#能夠成功刪除
[zk: localhost:2181(CONNECTED) 43] delete /merryyou/test/abc             
[zk: localhost:2181(CONNECTED) 46] ls /merryyou/test
[]
[zk: localhost:2181(CONNECTED) 47] 
#設置節點信息爲a admin
[zk: localhost:2181(CONNECTED) 47] setAcl /merryyou/test world:anyone:a  
cZxid = 0x200000018
ctime = Sat Jun 02 16:18:18 UTC 2018
mZxid = 0x200000018
mtime = Sat Jun 02 16:18:18 UTC 2018
pZxid = 0x20000001d
cversion = 2
dataVersion = 0
aclVersion = 3
ephemeralOwner = 0x0
dataLength = 4
numChildren = 0
#獲取 設置都提示權限不足
[zk: localhost:2181(CONNECTED) 49] get /merryyou/test
Authentication is not valid : /merryyou/test
[zk: localhost:2181(CONNECTED) 50] set /merryyou/test 123
Authentication is not valid : /merryyou/test
[zk: localhost:2181(CONNECTED) 51]
acl Auth 密碼明文設置
[zk: localhost:2181(CONNECTED) 53] create /niocoder/merryyou merryyou
Created /niocoder/merryyou
#查詢默認節點權限信息
[zk: localhost:2181(CONNECTED) 54] getAcl /niocoder/merryyou
'world,'anyone
: cdrwa
[zk: localhost:2181(CONNECTED) 55] 
#使用auth設置節點權限信息
[zk: localhost:2181(CONNECTED) 2] setAcl /niocoder/merryyou auth:test:test:cdrwa  
Acl is not valid : /niocoder/merryyou
# 註冊test:test 帳號密碼
[zk: localhost:2181(CONNECTED) 3] addauth digest test:test
[zk: localhost:2181(CONNECTED) 4] setAcl /niocoder/merryyou auth:test:test:cdrwa
cZxid = 0x200000020
ctime = Sat Jun 02 16:32:08 UTC 2018
mZxid = 0x200000020
mtime = Sat Jun 02 16:32:08 UTC 2018
pZxid = 0x200000020
cversion = 0
dataVersion = 0
aclVersion = 1
ephemeralOwner = 0x0
dataLength = 8
numChildren = 0
#查詢節點權限信息 密碼爲密文格式
[zk: localhost:2181(CONNECTED) 5] getAcl /niocoder/merryyou
'digest,'test:V28q/NynI4JI3Rk54h0r8O5kMug=
: cdrwa
[zk: localhost:2181(CONNECTED) 6]
acl digest 密碼密文設置
[zk: localhost:2181(CONNECTED) 13] create /names test
Created /names
[zk: localhost:2181(CONNECTED) 14] getAcl /names
'world,'anyone
: cdrwa
#使用digest設置節點的權限信息 密碼爲test密文
[zk: localhost:2181(CONNECTED) 15] setAcl /names digest:test:V28q/NynI4JI3Rk54h0r8O5kMug=:cdra
cZxid = 0x400000006
ctime = Sun Jun 03 01:01:17 UTC 2018
mZxid = 0x400000006
mtime = Sun Jun 03 01:01:17 UTC 2018
pZxid = 0x400000006
cversion = 0
dataVersion = 0
aclVersion = 1
ephemeralOwner = 0x0
dataLength = 4
numChildren = 0
#查詢節點權限信息
[zk: localhost:2181(CONNECTED) 16] getAcl /names
'digest,'test:V28q/NynI4JI3Rk54h0r8O5kMug=
: cdra
#獲取節點信息提示權限不足
[zk: localhost:2181(CONNECTED) 5] get /names
Authentication is not valid : /names
# 註冊帳戶
[zk: localhost:2181(CONNECTED) 4] addauth digest test:test
# 能夠正常獲取
[zk: localhost:2181(CONNECTED) 17] get /names          
test
cZxid = 0x400000006
ctime = Sun Jun 03 01:01:17 UTC 2018
mZxid = 0x400000006
mtime = Sun Jun 03 01:01:17 UTC 2018
pZxid = 0x400000006
cversion = 0
dataVersion = 0
aclVersion = 1
ephemeralOwner = 0x0
dataLength = 4
numChildren = 0
#因爲沒有設置寫權限不能修改節點 w
[zk: localhost:2181(CONNECTED) 18] set /names 111
Authentication is not valid : /names
[zk: localhost:2181(CONNECTED) 19] delete /names
[zk: localhost:2181(CONNECTED) 20]
acl ip 控制客戶端
[zk: localhost:2181(CONNECTED) 22] create /niocoder/ip aa
Created /niocoder/ip
[zk: localhost:2181(CONNECTED) 23] get /niocoder/ip
aa
cZxid = 0x40000000a
ctime = Sun Jun 03 01:06:47 UTC 2018
mZxid = 0x40000000a
mtime = Sun Jun 03 01:06:47 UTC 2018
pZxid = 0x40000000a
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 2
numChildren = 0
# 添加ip控制的權限信息
[zk: localhost:2181(CONNECTED) 24] setAcl /niocoder/ip ip:192.168.0.68:cdrwa
cZxid = 0x40000000a
ctime = Sun Jun 03 01:06:47 UTC 2018
mZxid = 0x40000000a
mtime = Sun Jun 03 01:06:47 UTC 2018
pZxid = 0x40000000a
cversion = 0
dataVersion = 0
aclVersion = 1
ephemeralOwner = 0x0
dataLength = 2
numChildren = 0
[zk: localhost:2181(CONNECTED) 25] getAcl /niocoder/ip
'ip,'192.168.0.68
: cdrwa
[zk: localhost:2181(CONNECTED) 26]
acl super超級管理員

使用super權限須要修改zkServer.sh，添加super管理員，重啓zkServer.shsql

"-Dzookeeper.DigestAuthenticationProvider.superDigest=test:V28q/NynI4JI3Rk54h0r8O5kMug="
 nohup "$JAVA" "-Dzookeeper.log.dir=${ZOO_LOG_DIR}" "-Dzookeeper.root.logger=${ZOO_LOG4J_PROP}" "-Dzookeeper.DigestAuthenticationprovider.superDigest=test:V28q/NynI4JI3Rk54h0r8O5kMug=" \
    -cp "$CLASSPATH" $JVMFLAGS $ZOOMAIN "$ZOOCFG" > "$_ZOO_DAEMON_OUT" 2>&1 < /dev/null &

#重啓進入zkCli
#因爲以前設置ip權限，因此不容許訪問
[zk: localhost:2181(CONNECTED) 2] ls /niocoder/ip
Authentication is not valid : /niocoder/ip
#登陸帳號信息，即爲管理員帳號
[zk: localhost:2181(CONNECTED) 3] addauth digest test:test
#正常訪問，節點內容爲空
[zk: localhost:2181(CONNECTED) 4] ls /niocoder/ip
[]
[zk: localhost:2181(CONNECTED) 5] get /niocoder/ip
aa
cZxid = 0x40000000a
ctime = Sun Jun 03 01:06:47 UTC 2018
mZxid = 0x40000000a
mtime = Sun Jun 03 01:06:47 UTC 2018
pZxid = 0x40000000a
cversion = 0
dataVersion = 0
aclVersion = 1
ephemeralOwner = 0x0
dataLength = 2
numChildren = 0
[zk: localhost:2181(CONNECTED) 6]

四字命令Four Letter Words

  • 使用四字命令須要安裝nc命令,(yum install nc)
stat 查看狀態信息
[root@localhost bin]# echo stat | nc 192.168.0.68 2181
Zookeeper version: 3.4.11-37e277162d567b55a07d1755f0b31c32e93c01a0, built on 11/01/2017 18:06 GMT
Clients:
 /192.168.0.68:49346[0](queued=0,recved=1,sent=0)

Latency min/avg/max: 0/0/4
Received: 62
Sent: 61
Connections: 1
Outstanding: 0
Zxid: 0x50000000a
Mode: follower
Node count: 10
[root@localhost bin]#
ruok 查看zookeeper是否啓動
[root@localhost bin]# echo ruok | nc 192.168.0.68 2181
imok[root@localhost bin]#
dump 列出沒有處理的節點，臨時節點
imok[root@localhost bin]# echo dump | nc 192.168.0.68 2181
SessionTracker dump:
org.apache.zookeeper.server.quorum.LearnerSessionTracker@29805957
ephemeral nodes dump:
Sessions with Ephemerals (0):
[root@localhost bin]#
conf 查看服務器配置
[root@localhost bin]# echo conf | nc 192.168.0.68 2181
clientPort=2181
dataDir=/usr/home/zookeeper-3.4.11/data/version-2
dataLogDir=/usr/home/zookeeper-3.4.11/data/version-2
tickTime=2000
maxClientCnxns=60
minSessionTimeout=4000
maxSessionTimeout=40000
serverId=2
initLimit=10
syncLimit=5
electionAlg=3
electionPort=3888
quorumPort=2888
peerType=0
[root@localhost bin]#
cons 顯示鏈接到服務端的信息
[root@localhost bin]# echo cons | nc 192.168.0.68 2181
 /192.168.0.68:49354[0](queued=0,recved=1,sent=0)

[root@localhost bin]#
envi 顯示環境變量信息
[root@localhost bin]# echo envi | nc 192.168.0.68 2181
Environment:
zookeeper.version=3.4.11-37e277162d567b55a07d1755f0b31c32e93c01a0, built on 11/01/2017 18:06 GMT
host.name=localhost
java.version=1.8.0_111
java.vendor=Oracle Corporation
java.home=/usr/local/jdk1.8.0_111/jre
java.class.path=/usr/home/zookeeper-3.4.11/bin/../build/classes:/usr/home/zookeeper-3.4.11/bin/../build/lib/*.jar:/usr/home/zookeeper-3.4.11/bin/../lib/slf4j-log4j12-1.6.1.jar:/usr/home/zookeeper-3.4.11/bin/../lib/slf4j-api-1.6.1.jar:/usr/home/zookeeper-3.4.11/bin/../lib/netty-3.10.5.Final.jar:/usr/home/zookeeper-3.4.11/bin/../lib/log4j-1.2.16.jar:/usr/home/zookeeper-3.4.11/bin/../lib/jline-0.9.94.jar:/usr/home/zookeeper-3.4.11/bin/../lib/audience-annotations-0.5.0.jar:/usr/home/zookeeper-3.4.11/bin/../zookeeper-3.4.11.jar:/usr/home/zookeeper-3.4.11/bin/../src/java/lib/*.jar:/usr/home/zookeeper-3.4.11/bin/../conf:
java.library.path=/usr/java/packages/lib/amd64:/usr/lib64:/lib64:/lib:/usr/lib
java.io.tmpdir=/tmp
java.compiler=<NA>
os.name=Linux
os.arch=amd64
os.version=3.10.0-514.10.2.el7.x86_64
user.name=root
user.home=/root
user.dir=/usr/home/zookeeper-3.4.11/bin
[root@localhost bin]#
mntr 查看zk的健康信息
[root@localhost bin]# echo mntr | nc 192.168.0.68 2181
zk_version	3.4.11-37e277162d567b55a07d1755f0b31c32e93c01a0, built on 11/01/2017 18:06 GMT
zk_avg_latency	0
zk_max_latency	4
zk_min_latency	0
zk_packets_received	68
zk_packets_sent	67
zk_num_alive_connections	1
zk_outstanding_requests	0
zk_server_state	follower
zk_znode_count	10
zk_watch_count	0
zk_ephemerals_count	0
zk_approximate_data_size	124
zk_open_file_descriptor_count	32
zk_max_file_descriptor_count	4096
[root@localhost bin]#
wchs 展現watch的信息
[root@localhost bin]# echo wchs | nc 192.168.0.68 2181
0 connections watching 0 paths
Total watches:0
[root@localhost bin]#
wchc和wchp 顯示session的watch信息 path的watch信息
  • 須要在 配置zoo.cfg文件中添加 4lw.commands.whitelist=*
[root@localhost bin]# echo wchc | nc 192.168.0.68 2181
wchc is not executed because it is not in the whitelist.
[root@localhost bin]# echo wchp | nc 192.168.0.68 2181
wchp is not executed because it is not in the whitelist.

總結

熟悉zookeeper基礎命令操做後，再使用zookeeper提供的api或者第三方封裝的api,會感受一目瞭然。shell

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