Ok so I did a fresh CentOS 6.2 install, and setup KVM virtualization, setup a GuestOS with 20gb hard drive space just fine,

The 2nd Guest I wanted to have 50gb and it said "Sorry you only have 23gb avail, but it is a 320 gb harddrive with 260 gb free??

I dont know alot about partitioning so I go into hard disk utility and it has me setup as follows:

/dev/dm0 - 54gb
/dev/dm1 - 6.3gb
/dev/dm2 - 260 gb

so I know i have the storage. But when I go through the new VPS creation setup it only gives the option to decide how big the disk image is, not which partition it is located on...


How do I get KVM to use this 260gb partition for my guest os installations?

thanks

Can you provide some df -h output?

Also fdisk -l.

I would suspect that you have / mounted on /dev/dm0 and that /var is not on its own partition.
Your guest images will be stored by default in /var/lib/libvirt/images, which would mean you only have the 54GB filesystem to play with. Is /dev/dm2 mounted on /home or something?