zookeeper安装与配置
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一、环境
1.操作系统：centos 6
2.3台虚拟机，192.168.1.128，192.168.1.129，192.168.1.130
3.关闭防火墙
二、安装与配置步骤
1.下载zookeeper，如：zookeeper-3.4.6.tar.gz，放到/usr/local目录下，并解压
cd /usr/local/
tar zxvf zookeeper-3.4.6.tar.gz
2.目录修改为zookeeper
mv zookeeper-3.4.6 zookeeper
3.在/usr/local/zookeeper目录下，新建日志目录和日志目录
mkdir /usr/local/zookeeper/data
mkdir /usr/local/zookeeper/logs
4.配置文件修改与配置参数说明
4.1 配置修改
将/usr/local/zookeeper/conf下的zoo_sample.cfg重命名为zoo.cfg，配置文件内容如下：
# 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/zookeeper/data
dataLogDir=/usr/local/zookeeper/logs
# 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
server.1=192.168.1.128:2888:3888
server.2=192.168.1.129:2888:3888
server.3=192.168.1.130:2888:3888
4.2 配置参数说明
initLimit：zookeeper集群包含一台leader和多台follower，initLimit表示初始化连接时，follower和leader之间最长的心跳时间。
syncLimit：follower和leader之间发送消息，请求与应答的最大时间，即5x2000ms=10000ms=10s。
server.X=A:B:C 其中X是一个数字，表示第几号server，A是IP或者域名，B是该server和集群leader交换信息所用端口号，C是选择leader时所用端口号。
5.在/usr/local/zookeeper/data目录下，新建文件myid，
touch /usr/local/zookeeper/data/myid
对于192.168.1.128，myid文件内容为1，
对于192.168.1.129，myid文件内容为2，
对于192.168.1.130，myid文件内容为3
三、启动与关闭
启动：/usr/local/zookeeper/bin/zkServer.sh start
关闭：/usr/local/zookeeper/bin/zkServer.sh stop
重启：/usr/local/zookeeper/bin/zkServer.sh restart
查看：/usr/local/zookeeper/bin/zkServer.sh status
