使用ambari快速部署Hadoop集群需要先看清适用场景和关键步骤，避免只记结论却忽略实际限制。

基础环境准备

在所有节点都执行ssh-keygen -t rsa 生成Key

[root@linux-node1 ~]# ssh-keygen -t rsaGenerating public/private rsa key pair.Enter file in which to save the key (/root/.ssh/id_rsa): Enter passphrase (empty for no passphrase): Enter same passphrase again: Your identification has been saved in /root/.ssh/id_rsa.Your public key has been saved in /root/.ssh/id_rsa.pub.

虽然除了Server端之外其它节点可以不执行，但是ssh-keygen命令会帮我们创建相应的目录并设置权限，不在需要我们手动操作。

将Ambari Server的公钥scp到其它节点上

[root@linux-node1 ~]# scp .ssh/id_rsa.pub 192.168.56.12:/root/.ssh/authorized_keys

设置权限

[root@linux-node2 ~]# chmod 600 ~/.ssh/authorized_keys

测试连接

[root@linux-node1 ~]# ssh 192.168.56.12Last login: Sat Apr2 16:42:46 2016 from 192.168.56.1[root@linux-node2 ~]#

设置完毕无密码登录后，我们就可以开始部署ambari-server了。

安装jdk

由于ambari安装过程中的jdk下载比较缓慢，所以我们可以直接使用yum仓库里面的openjdk

[root@linux-node1 ~]# yum install -y java-1.8.0

部署ambari-server

ambari-server的部署比较简单，很多实用实用默认即是最好的选择。

安装ambari-server

[root@test-node3 ~]# cd /etc/yum.repos.d/# wget http://public-repo-1.hortonworks.com/ambari/centos7/2.x/updates/2.2.0.0/ambari.repo# yum install -y ambari-server

设置ambari-server

安装完毕后，需要使用ambari-server setup命令进行设置，均可以使用默认设置，直接回车即可。

[root@linux-node1 ~]# ambari-server setupUsing python/usr/bin/python2Setup ambari-serverChecking SELinux...SELinux status is 'disabled'Customize user account for ambari-server daemon [y/n](n)? Adjusting ambari-server permissions and ownership...Checking firewall status...Redirecting to /bin/systemctl statusiptables.serviceChecking JDK...[1] Oracle JDK 1.8   Java Cryptography Extension (JCE) Policy Files 8[2] Oracle JDK 1.7   Java Cryptography Extension (JCE) Policy Files 7[3] Custom JDK===========================================================================Enter choice (1): 3WARNING: JDK must be installed on all hosts and JAVA_HOME must be valid on all hosts.WARNING: JCE Policy files are required for configuring Kerberos security. If you plan to use Kerberos,please make sure JCE Unlimited Strength Jurisdiction Policy Files are valid on all hosts.Path to JAVA_HOME: /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.77-0.b03.el7_2.x86_64/jre/Validating JDK on Ambari Server...done.Completing setup...Configuring database...Enter advanced database configuration [y/n](n)?Configuring database...Default properties detected. Using built-in database.Configuring ambari database...Checking PostgreSQL...Running initdb: This may take upto a minute.Initializing database ... OKAbout to start PostgreSQLConfiguring local database...Connecting to local database...done.Configuring PostgreSQL...Restarting PostgreSQLExtracting system views...ambari-admin-2.2.0.0.1310.jar......Adjusting ambari-server permissions and ownership...Ambari Server 'setup' completed successfully.

启动ambari-server

[root@linux-node1 ~]# ambari-server start

查看监听端口

[root@linux-node1 ~]# netstat -ntlp | grep 8080tcp6 00 :::8080 :::*LISTEN24168/java

访问ambari server

现在可以在浏览器访问你的ambari server了。注意端口是8080。

http://192.168.56.11:8080/

默认的用户名和密码都是admin

创建Hadoop集群

登录 Ambari 之后，点击按钮“Launch Install Wizard”，就可以开始创建属于自己的大数据平台。

1.设置集群的名称

2.选择一个Stack，默认使用最新版本。

3.填写你环境的所有主机名，并上传验证的公钥。注意使用FQDN名称，并且主机名要能够解析。

4.选择需要安装的组件

5.角色分配

其它步骤均使用默认配置即可。