[tlug] Xen advice, please

[mcooper <mcooper@example.com>]

I would really love to get advice on Xen, particularly an opinion on  
whether  or not I should try to use it here. Purchasing VMWare  
licenses is out of the question for us, and VMWare says that their  
free server product is not for production.

In January 2008, I will have to migrate the functionality of six old  
servers over to four new servers and send the four old servers back  
to the lease company. We use RHEL3 (five boxes) and RHEL4 (one box)  
right now.

Due to grant and accounting circumstances, I had to buy one server  
ahead of time, so I have this big, bad, empty server for a year  
before the migration has to happen. This will also be my first time  
doing such a migration, and I have no assistance or guidance... an  
educational experience I am looking forward to.

Since I have a 4GB RAM server with ample disk space right now, I was  
thinking I could install RHEL5 (which includes Xen) and then make  
virttual RHEL machines of each server that will have to be migrated.  
I would be able to take my time getting it right, and when the new  
machines come, I could just move the virtual machines over to the new  
boxes.

Instead of waiting for the new machines to arrive to work out OS  
upgrading and migrating issues, I was thinking that Xen would allow  
me to migrate the systems ahead of time and then have a more flexible  
installation when I am done.

Am I being unrealistic or unwise?

Is Xen ready for production use?

Are there any complications with post-catastrophy situations when  
using Xen? Does Xen complicate using backups to rebuild systems? I  
plan to use rsnapshot on the backup server to backup data every  
night, and I also want to have a bare-metal backup. I assume that  
having a bare metal backup copy of the host server include the VMs  
with no problems.

Before I spend time installing Xen and VMs, I would like to know if  
this is an advisable direction.

Micheal