Hadoop集群(一) Zookeeper搭建

作为Hadoop初学者，自然要从安装入手。而hadoop的优势就是分布式，所以，也一定要安装分布式的系统。

整体安装步骤，包括Zookeeper+HDFS+Hbase，为了文章简洁，我会分三篇blog记录我的安装步骤。

本文记录的是集群环境准备，zookeeper的安装步骤。

~~~~~~~~~~~环境准备部分~~~~~~~~~~~~~~~~~

IP部署规划（准备了三个虚拟机，操作系统是Centos6.7）

Zookeeper主机分配

192.168.67.101 c6701192.168.67.102 c6702192.168.67.103 c6703

HDFS主机分配

192.168.67.101 c6701 --Namenode+datanode192.168.67.102 c6702 --datanode192.168.67.103 c6703 --datanode

Hbase主机分配

192.168.67.101 c6701 --Master + region192.168.67.102 c6702 --region192.168.67.103 c6703 --region

1. 为了分别管理各个服务，我为每个服务，都单独创建了用户.

创建的用户有:

zk

hdfs

hbase

2. 为每一个用户创建ssh免密,并分发到全部节点，这样，我就只在C6701上执行命令，通过远程的方式安装C6702和C6703

ssh-keygen -t rsa -f ~/.ssh/id_rsa

拷贝密钥到全部节点即可（只有c6701访问02和03不需要密码，反向访问是需要密码的）

ssh-copy-id  c6701

ssh-copy-id  c6702

ssh-copy-id  c6703

3. 强调一下，/etc/hosts 需要设置

[root@c6701 ~]# more /etc/hosts 192.168.67.101 c6701.org c6701192.168.67.102 c6702.org c6702192.168.67.103 c6703.org c6703

4. 下面在C6701执行，中间会调用ssh远程执行一些命令,验证ssh免密是否生效

ssh c6702 "cat /proc/cpuinfo"

ssh c6702 "hostname"

5. 下载安装软件（内网地址）

cd /tmp/software

wget http://192.21.104.48/deploy/jdk-8u144-linux-x64.tar.gz

wget http://192.21.104.48/deploy/zookeeper-3.4.6.tar.gz

wget http://192.21.104.48/deploy/hbase-1.1.3.tar.gz

wget http://192.21.104.48/deploy/hadoop-2.6.0-EDH-0u2.tar.gz

wget http://192.21.104.48/deploy/hadoop-2.7.1.tar.gz

6. 安装JDK，全部节点都要安装

#tar -xzvf  jdk-8u144-linux-x64.tar.gz -C /usr/local

7. 添加下面信息到.bash_profile

export JAVA_HOME=/usr/local/jdk1.8.0_144

export JRE_HOME=/usr/local/jdk1.8.0_144/jre

export CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar:$JRE_HOME/lib:$CLASSPATH

export PATH=$JAVA_HOME/bin:$PATH

source /etc/profile

8. 检查版本信息

# java -version

java version "1.8.0_144"

Java(TM) SE Runtime Environment (build 1.8.0_144-b01)

Java HotSpot(TM) 64-Bit Server VM (build 25.144-b01, mixed mode)

~~~~~~~~~~~zookeeper的安装部分~~~~~~~~~~~~~~~~~

1. 在C6701安装Zookeeper

useradd zk

echo "zk:zk" | chpasswd

su - zk

mkdir zk

tar -zxvf /tmp/software/zookeeper-3.4.6.tar.gz -C /home/zk/zk

~~~~~~~~~~~~~zoo.cfg的配置~~~~~~~~~~~~~~~

$ pwd/home/zk/zk/zookeeper-3.4.6/conf/zoo.cfg

$ cat /home/zk/zk/zookeeper-3.4.6/conf/zoo.cfg |grep -v '^#'

tickTime=2000

initLimit=10

syncLimit=5

dataDir=/data/zookeeper/data

dataLogDir=/data/zookeeper/log

clientPort=2181

autopurge.snapRetainCount=3

autopurge.purgeInterval=6

server.1=c6701:2888:3888

server.2=c6702:2888:3888

server.3=c6703:2888:3888~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

2. 根据zoo.cfg创建data和log两个文件夹

#mkdir -p /data/zookeeper/data#mkdir -p /data/zookeeper/log#chown -R zk:zk /data/zookeeper#chown -R zk:zk /data/zookeeper/data#chown -R zk:zk /data/zookeeper/log

3.在zookeeper的目录中，创建上述两个文件夹。进入zkdata文件夹，创建文件myid，填入1。这里写入的1，是在zoo.cfg文本中的server.1中的1。当我们把所有文件都配置完毕，我们把hadoop1中yarn目录复制到其它机器中，我们在修改每台机器中对应的myid文本，hadoop2中的myid写入2。其余节点，安照上面配置，依此写入相应的数字。Zkdatalog文件夹，是为了指定zookeeper产生日志指定相应的路径。

# su - zk -c "echo 1 > /data/zookeeper/data/myid"

4. 添加环境变量,在/etc/profile目录中,将ZOOKEEPER_HOME/bin在原有的PATH后面加入":$ZOOKEEPER_HOME/bin"

关于环境变量修改/etc目录下的profile文件，也可以在根目录下的.bashrc目录下添加环境变量。这两者有什么区别：.bashrc是对当前目录用户的环境变量，profile文件是对所有用户都开放的目录。当系统加载文件中，先从profile找相应的路劲，如果没有会在.bashrc文件中找对应的环境变量路径。这两者大家稍至了解。

然后 source /etc/profile

5. 安装c6702的zookeeper

#ssh c6702 "useradd zk"#ssh c6702 "echo "zk:zk" | chpasswd"

为zk用户ssh免密

#ssh-copy-id  zk@c6702

拷贝软件

#scp -r /tmp/software/hadoop-* root@c6702:/tmp/software#ssh c6702 "chmod 777 /tmp/software/*"

创建目录，解压软件

#ssh zk@c6702 "mkdir zk"#ssh zk@c6702 "tar -zxvf /tmp/software/zookeeper-3.4.6.tar.gz -C /home/zk/zk"#ssh zk@c6702 "ls -al zk"#ssh zk@c6702 "ls -al zk/zookeeper*"#ssh zk@c6702 "rm /home/zk/zk/zookeeper-3.4.6/conf/zoo.cfg"#scp -r /home/zk/zk/zookeeper-3.4.6/conf/zoo.cfg zk@c6702:/home/zk/zk/zookeeper-3.4.6/conf/.#ssh zk@c6702 "cat /home/zk/zk/zookeeper-3.4.6/conf/zoo.cfg |grep -v '^#'"

根据zoo.cfg创建目录#ssh c6702 "mkdir -p /data/zookeeper/data"#ssh c6702 "chown -R zk:zk /data/zookeeper"#ssh c6702 "chown -R zk:zk /data/zookeeper/data"#ssh c6702 "mkdir -p /data/zookeeper/log" #ssh c6702 "chown -R zk:zk /data/zookeeper/log"

创建文件myid，填入2

ssh zk@c6702  "echo 2 > /data/zookeeper/data/myid"

6. 安装c6703的zookeeper

#ssh c6703 "useradd zk"#ssh c6703 "echo "zk:zk" | chpasswd"

为zk用户ssh免密

ssh-copy-id  zk@c6703

拷贝软件

#scp -r /tmp/software/hadoop-* root@c6703:/tmp/software#ssh c6703 "chmod 777 /tmp/software/*"

创建目录，解压软件

#ssh zk@c6703 "mkdir zk"#ssh zk@c6703 "tar -zxvf /tmp/software/zookeeper-3.4.6.tar.gz -C /home/zk/zk"#ssh zk@c6703 "ls -al zk"#ssh zk@c6703 "ls -al zk/zookeeper*"#ssh zk@c6703 "rm /home/zk/zk/zookeeper-3.4.6/conf/zoo.cfg"#scp -r /home/zk/zk/zookeeper-3.4.6/conf/zoo.cfg zk@c6703:/home/zk/zk/zookeeper-3.4.6/conf/.#ssh zk@c6703 "cat /home/zk/zk/zookeeper-3.4.6/conf/zoo.cfg |grep -v '^#'"

根据zoo.cfg创建目录

#ssh c6703 "mkdir -p /data/zookeeper/data"#ssh c6703 "chown -R zk:zk /data/zookeeper"#ssh c6703 "chown -R zk:zk /data/zookeeper/data"#ssh c6703 "mkdir -p /data/zookeeper/log" #ssh c6703 "chown -R zk:zk /data/zookeeper/log"

创建文件myid，填入3

ssh zk@c6703  "echo 3 > /data/zookeeper/data/myid"

7. 启动ZK

/home/zk/zk/zookeeper-3.4.6/bin/zkServer.sh start/home/zk/zk/zookeeper-3.4.6/bin/zkServer.sh status

远程启动命令

ssh zk@c6702 "/home/zk/zk/zookeeper-3.4.6/bin/zkServer.sh\ start"

ssh zk@c6703 "/home/zk/zk/zookeeper-3.4.6/bin/zkServer.sh\ start"

ssh zk@c6702 "/home/zk/zk/zookeeper-3.4.6/bin/zkServer.sh\ status"

ssh zk@c6703 "/home/zk/zk/zookeeper-3.4.6/bin/zkServer.sh\ status"

8. 没有全部启动三个ZK前的状态

[vagrant@c7003 bin]$ ./zkServer.sh status

ZooKeeper JMX enabled by defaultUsing config: /home/vagrant/zookeeper-3.4.10/bin/../conf/zoo.cfg

Error contacting service. It is probably not running.

9. 需要将三个ZK全启动之后，才能选举出leader

$ ./zkServer.sh status

ZooKeeper JMX enabled by defaultUsing config: /home/vagrant/zookeeper-3.4.10/bin/../conf/zoo.cfgMode: follower[vagrant@c7002 bin]$ ./zkServer.sh status

ZooKeeper JMX enabled by defaultUsing config: /home/vagrant/zookeeper-3.4.10/bin/../conf/zoo.cfgMode: leader

=======2018.1.13更新==========

客户端连接方式

客户端是随机顺序的方式连接server的，无法指定，或者优先读哪个一个zookeeper server。

./zkCli.sh -server c6701:2181,c6702:2181,c6703:2181

输出如下：

第一次连接，连接到c6701上

[zookeeper@c6702 bin]$ /usr/local/hadoop/zookeeper-3.4.6/bin/zkCli.sh -server c6701:2181,c6702:2181,c6703:2181

Connecting to c6701:2181,c6702:2181,c6703:2181......2018-01-11 21:07:30,797 [myid:] - INFO  [main:ZooKeeper@438] - Initiating client connection, connectString=c6701:2181,c6702:2181,c6703:2181 sessionTimeout=30000 watcher=org.apache.zookeeper.ZooKeeperMain$MyWatcher@4b4bc1e

Welcome to ZooKeeper!2018-01-11 21:07:30,830 [myid:] - INFO  [main-SendThread(c6701.python279.org:2181):ClientCnxn$SendThread@975] - Opening socket connection to server c6701.python279.org/192.168.67.101:2181. Will not attempt to authenticate using SASL (unknown error)

JLine support is enabled2018-01-11 21:07:30,873 [myid:] - INFO  [main-SendThread(c6701.python279.org:2181):ClientCnxn$SendThread@852] - Socket connection established to c6701.python279.org/192.168.67.101:2181, initiating session2018-01-11 21:07:30,916 [myid:] - INFO  [main-SendThread(c6701.python279.org:2181):ClientCnxn$SendThread@1235] - Session establishment complete on server c6701.python279.org/192.168.67.101:2181, sessionid = 0x160e70285f70001, negotiated timeout = 30000

WATCHER::

WatchedEvent state:SyncConnected type:None path:null

第二次连接，连接到c6702上

Connecting to c6701:2181,c6702:2181,c6703:2181......2018-01-11 21:10:18,442 [myid:] - INFO  [main:ZooKeeper@438] - Initiating client connection, connectString=c6701:2181,c6702:2181,c6703:2181 sessionTimeout=30000 watcher=org.apache.zookeeper.ZooKeeperMain$MyWatcher@4b4bc1e

Welcome to ZooKeeper!2018-01-11 21:10:18,489 [myid:] - INFO  [main-SendThread(c6702.python279.org:2181):ClientCnxn$SendThread@975] - Opening socket connection to server c6702.python279.org/192.168.67.102:2181. Will not attempt to authenticate using SASL (unknown error)

JLine support is enabled2018-01-11 21:10:18,508 [myid:] - INFO  [main-SendThread(c6702.python279.org:2181):ClientCnxn$SendThread@852] - Socket connection established to c6702.python279.org/192.168.67.102:2181, initiating session2018-01-11 21:10:18,561 [myid:] - INFO  [main-SendThread(c6702.python279.org:2181):ClientCnxn$SendThread@1235] - Session establishment complete on server c6702.python279.org/192.168.67.102:2181, sessionid = 0x260e70284650002, negotiated timeout = 30000

WATCHER::

WatchedEvent state:SyncConnected type:None path:null

至此，基础环境部署完。并且zookeeper也安装完成。下面我们会在下一篇文章中，继续安装HDFS。