# yum grouplist

Installed Groups:
   Administration Tools
   Compatibility Arch Support
   Editors
   MySQL Database
   Server Configuration Tools
   System Tools
   Text-based Internet
   Web Server
   Windows File Server
   X Window System

Available Groups:
   AptRPM
   Authoring and Publishing
   Compatibility Arch Development Support
   DNS Name Server
   Development Tools
   Engineering and Scientific
   FTP Server
   GNOME Desktop Environment
   GNOME Software Development
   Games and Entertainment
   Graphical Internet
   Graphics
   Horde-Apps
   KDE (K Desktop Environment)
   KDE Software Development
   Legacy Network Server
   Legacy Software Development
   Mail Server
   Network Servers
   News Server
   Office/Productivity
   PostgreSQL Database
   Printing Support
   Sound and Video
   X Software Development
   XFCE-4.2
   drbd-heartbeat

Done

# yum groupinfo Virtualization

# yum info xen

# yum groupinstall Virtualization