1.检查发现缺少xorg-x11-apps-7.4-10.el6.x86_64
[root@js Desktop]# rpm -qa|grep server evolution-data-server-2.28.3-15.el6.x86_64 obex-data-server-0.4.3-4.el6.x86_64 xorg-x11-server-common-1.10.6-1.el6.x86_64 xorg-x11-server-Xorg-1.10.6-1.el6.x86_64 openssh-server-5.3p1-81.el6.x86_64 xorg-x11-server-utils-7.5-5.2.el6.x86_64 redhat-release-server-6Server-6.3.0.3.el6.x86_64
2.配置yum源，安装xorg-x11-apps-7.4-10.el6.x86_64
配置yum本地源 http://www.cnblogs.com/jusonsummer/p/4842508.html
[root@js yum.repos.d]# yum install xorg-x11-apps*
3.验证 xclock
bash: xclock: command not found
原文：http://www.cnblogs.com/jusonsummer/p/4842516.html