CDH localhost:7180 页面没法打开

有时会遇到CDH集群的7180页面没法访问，经过命令查看服务发现：

1 service --status-all 
2 cloudera-scm-server dead but pid file exists

删除pid文件：　

1 rm -rf /var/run/cloudera-scm-server 　

而后启动服务cloudera-scm-server时会遇到过一段时间本身挂掉，并返回cloudera-scm-server dead but pid file exists的问题，主要是在cloudera-scm-server-db没有正常启动的状况，表现为以下状况：

 1 [root@gyvm-4 data]# service cloudera-scm-server start  
 2 Starting cloudera-scm-server:                              [  OK  ]  
 3 [root@gyvm-4 data]#   
 4 [root@gyvm-4 data]# service cloudera-scm-server status  
 5 cloudera-scm-server (pid  60761) is running...  
 6 [root@gyvm-4 data]# service cloudera-scm-server status  
 7 cloudera-scm-server (pid  60761) is running...  
 8 [root@gyvm-4 data]# service cloudera-scm-server status  
 9 cloudera-scm-server (pid  60761) is running...  
10 [root@gyvm-4 data]# service cloudera-scm-server status  
11 cloudera-scm-server dead but pid file exists  

这时候想要完整重启cloudera-scm server-db/server，发现cloudera-scm-server-db没法重启

1 [root@gyvm-4 data]# service cloudera-scm-server-db stop
2 waiting for server to shut down............................................................... failed
3 pg_ctl: server does not shut down

没法中止server-db的缘由是残留了一个pid文件，status显示不正确，删除该文件，经过status查看，server-db其实已经中止了。

1 [root@gyvm-4 data]# cd /var/lib/cloudera-scm-server-db/data  
2 [root@gyvm-4 data]# service cloudera-scm-server-db status  
3 pg_ctl: server is running (PID: 17378)  
4 /usr/bin/postgres "-D" "/var/lib/cloudera-scm-server-db/data"  
5 [root@gyvm-4 data]# rm postmaster.pid 6 rm: remove regular file `postmaster.pid'? y  
7 [root@gyvm-4 data]# service cloudera-scm-server-db status  
8 pg_ctl: no server running  

再次开启server-db，成功，启动server，成功。

1 [root@gyvm-4 data]# service cloudera-scm-server-db start  
2 DB initialization done.  
3 waiting for server to start.... done  
4 server started  
5 [root@gyvm-4 data]# service cloudera-scm-server start  
6 Starting cloudera-scm-server:                              [  OK  ]  

【结论】

　　究其缘由，是cloudera-server-db没有正常启动，可是残留了pid文件postmaster.pid，因此查看cloudera-server-db状态时，显示有误，返回cloudera-server-db是启动的状态。在此基础上，每次启动cloudera-server就会失败。

转自：http://blog.csdn.net/c1990/article/details/54706330