[CentOS-virt] Xen Database vms

[compdoc]

-----Original Message-----
From: centos-virt-bounces at centos.org
[mailto:centos-virt-bounces at centos.org] On Behalf Of Ben M.
Sent: Friday, January 15, 2010 10:17 AM
To: Discussion about the virtualization on CentOS
Subject: Re: [CentOS-virt] Xen Database vms


Thank you. Excellent thoughts all, and just the type of
feedback I
needed to think about. I would be going out a dedicated NIC
on the data
traffic, and I would do block devices in LVM for the disk
IO, Windows
2008 32bit seems to be very happy with that setup in a mixed
Xen
environment. Under no circumstances would I run these as
file images. 
There is no comparison to dedicated hardware for this
application using 
file based vms. Has to be block devices.

I think for my purposes putting the database servers in Xen
is
absolutely worth a shot. If it works, I have a lot of
benefits from it.
If it doesn't, I lost some hours but gained some knowledge,
and maybe a 
backup server.

A vpn (OpenVPN) server in Xen is part of my plan as well.
I'm trying to
sketch out all the lines of IO and see what I have to do to
keep things
snappy.
_______________________________________________


By the way, if the articles on the web are true, Red Hat is
going KVM for several reasons so I decided to go KVM only. 

For one thing, Xen requires a modified kernel on the host.
Also, I found I had to install drivers to get stats and
performance from xen, and sometimes the drivers wouldn't
install on some linux distros used in guests. 

But with kvm, I don't need to install drivers for kvm
guests. The virtual hardware presented to the OS must be
done right. And theres a choice of nics that don't need
additional drivers: realtek 8169, Intel e1000, etc.