使用xshell连接RHEL5.8服务器，敲入xclock命令想验证图形化安装条件，但是显示无此命令。
[root@template ~]# xclock
-bash: xclock: command not found
原来这台服务器没有安装xclock，使用yum安装记录如下：
[root@localhost ~]# yum install xorg-x11-apps
Loaded plugins: katello, product-id, security, subscription-manager
Updating certificate-based repositories.
Unable to read consumer identity
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package xorg-x11-apps.x86_64 0:7.1-4.0.1.el5 set to be updated
--> Finished Dependency Resolution Dependencies Resolved ===============================================================================================================================================================================================
Package Arch Version Repository Size
===============================================================================================================================================================================================
Installing:
xorg-x11-apps x86_64 7.1-4.0.1.el5 base 265 k Transaction Summary
===============================================================================================================================================================================================
Install 1 Package(s)
Upgrade 0 Package(s) Total download size: 265 k
Is this ok [y/N]: y
Downloading Packages:
xorg-x11-apps-7.1-4.0.1.el5.x86_64.rpm | 265 kB 00:00
Running rpm_check_debug
Running Transaction Test
Finished Transaction Test
Transaction Test Succeeded
Running Transaction
Installing : xorg-x11-apps 1/1
Installed products updated. Installed:
xorg-x11-apps.x86_64 0:7.1-4.0.1.el5 Complete!
完成后再次在终端中敲入xclock命令弹出了可爱的钟表。