zk安装与初体验

安装zk

brew install zookeeper

安装后默认目录为

/usr/local/Cellar/zookeeper/3.4.9

zk启动 停止

1.

cd /usr/local/Cellar/zookeeper/3.4.9/bin

2.

./zkServer start

ZooKeeper JMX enabled by default

Using config: /usr/local/etc/zookeeper/zoo.cfg

Starting zookeeper … STARTED

停止zk

./zkServer stop

终端如下显示

➜  bin ./zkServer stop

ZooKeeper JMX enabled by default

Using config: /usr/local/etc/zookeeper/zoo.cfg

Stopping zookeeper ... STOPPED

➜  bin

3.默认配置

cd  /usr/local/etc/zookeeper

# The number of milliseconds of each tick
tickTime=2000
# The number of ticks that the initial
# synchronization phase can take
initLimit=10
# The number of ticks that can pass between
# sending a request and getting an acknowledgement
syncLimit=5
# the directory where the snapshot is stored.
# do not use /tmp for storage, /tmp here is just
# example sakes.
dataDir=/usr/local/var/run/zookeeper/data
# the port at which the clients will connect
clientPort=2181
# the maximum number of client connections.
# increase this if you need to handle more clients
#maxClientCnxns=60
#
# Be sure to read the maintenance section of the
# administrator guide before turning on autopurge.
#
# http://zookeeper.apache.org/doc/current/zookeeperAdmin.html#sc_maintenance #
# The number of snapshots to retain in dataDir
#autopurge.snapRetainCount=3
# Purge task interval in hours
# Set to "0" to disable auto purge feature
#autopurge.purgeInterval=1

4.zk一些简单的命令

conf 输出相关服务配置的详细信息。

cons 列出所有连接到服务器的客户端的完全的连接 / 会话的详细信息。包括“接受 / 发送”的包数量、会话 id 、操作延迟、最后的操作执行等等信息。

dump 列出未经处理的会话和临时节点。

envi 输出关于服务环境的详细信息（区别于 conf 命令）

reqs 列出未经处理的请求

ruok 测试服务是否处于正确状态。如果确实如此，那么服务返回“imok ”，否则不做任何相应。

stat 输出关于性能和连接的客户端的列表。

wchs 列出服务器 watch 的详细信息。

wchc 通过 session 列出服务器 watch 的详细信息，它的输出是一个与watch 相关的会话的列表。

wchp 通过路径列出服务器 watch 的详细信息。它输出一个与 session相关的路径。

用法 echo conf | nc localhost 2181

clientPort=2181

dataDir=/usr/local/var/run/zookeeper/data/version-2

dataLogDir=/usr/local/var/run/zookeeper/data/version-2

tickTime=2000

maxClientCnxns=60

minSessionTimeout=4000

maxSessionTimeout=40000

serverId=0

echo dump | nc 127.0.0.1 2181
SessionTracker dump:
Session Sets (0):
ephemeral nodes dump:
Sessions with Ephemerals (0):

启动zk后，输入以下命令

./zkCli.sh -server localhost:2181

终端输出：

./zkCli -server 127.0.0.1:2181
Connecting to 127.0.0.1:2181
Welcome to ZooKeeper!
JLine support is enabled
[zk: 127.0.0.1:2181(CONNECTING) 0]
WATCHER::

WatchedEvent state:SyncConnected type:None path:null

此时连接到 zk服务器， 输入help 得到以下内容

[zk: 127.0.0.1:2181(CONNECTED) 1] 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: 127.0.0.1:2181(CONNECTED) 2]

用ls查看zk服务器的目录

[zk: 127.0.0.1:2181(CONNECTED) 5] ls/
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

创建新的节点

create /zk myData

再次输入 发现此时zk节点已经被创建

[zk: 127.0.0.1:2181(CONNECTED) 6] ls /
[zk, zookeeper]
[zk: 127.0.0.1:2181(CONNECTED) 7]

通过 get /zk 来查看刚才创建的是否包含myData 字符串

[zk: 127.0.0.1:2181(CONNECTED) 7] get /zk
myData
cZxid = 0x6
ctime = Sun Nov 20 19:16:04 CST 2016
mZxid = 0x6
mtime = Sun Nov 20 19:16:04 CST 2016
pZxid = 0x6
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 6
numChildren = 0

通过 set /zk naonao 可以对刚才的关联字符串进行修改

[zk: 127.0.0.1:2181(CONNECTED) 8] set /zk naonao
cZxid = 0x6
ctime = Sun Nov 20 19:16:04 CST 2016
mZxid = 0x7
mtime = Sun Nov 20 19:36:52 CST 2016
pZxid = 0x6
cversion = 0
dataVersion = 1
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 6
numChildren = 0

再次查看 get /zk

[zk: 127.0.0.1:2181(CONNECTED) 10] get /zk
naonao
cZxid = 0x6
ctime = Sun Nov 20 19:16:04 CST 2016
mZxid = 0x7
mtime = Sun Nov 20 19:36:52 CST 2016
pZxid = 0x6
cversion = 0
dataVersion = 1
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 6
numChildren = 0

删除zk delete /zk

[zk: 127.0.0.1:2181(CONNECTED) 11] delete /zk
[zk: 127.0.0.1:2181(CONNECTED) 12] ls /
[zookeeper]
[zk: 127.0.0.1:2181(CONNECTED) 13]