转为root，

yum install firefox

但是随即出现问题：

(firefox:4871): GnomeUI-WARNING **: While connecting to session manager:

None of the authentication protocols specified are supported.

/usr/lib/firefox/firefox: symbol lookup error: /usr/lib/libgdk-x11-2.0.so.0: undefined symbol: _XGetRequest

yum真不是个好东西。。。

google被墙，百度找不到，辗转到yahoo日本去找。

找到：

 - 

nixcraft.com/.../19976-Problem-With-VNC-refreshing-(Centos... - 

/usr/bin/gnome-session: symbol lookup error: /usr/lib64/libgdk-x11-2.0.so.0: undefined symbol: _XGetRequest (nautilus:17444): EggSMClient-WARNING **: Failed to connect to the session manager: IO error occured opening ...

地址：http://nixcraft.com/showthread.php/19976-Problem-With-VNC-refreshing-(Centos-6-2)

正文太长懒得看，反正有一样的错误，直接看解决方案：

 Solved

I figrued out what was going wrong. After looking into the log file and finding that error message, I was able to deduce that I need to upade xlibs. Once this was done everything worked fine.

For anyone that runs into this issue run this command:

yum install libX11

解决。