Anyone Actually Using Virtual Linux Servers?

[Jarod Wilson]

On Sep 08, 2007, at 22:50, Kristian Erik Hermansen wrote:

> On 9/8/07, Kent Borg <kentborg-KwkGvOEf1og at public.gmane.org> wrote:
>> Is anyone actually using virtual Linux servers?
>
> I built a project to run 4096 simultaneous guest machines on top of 64
> physical Linux servers using VMware...
>
> http://video.vmware.com/kickapps/service/ 
> displayMediaPlayPage.kickAction? 
> mediaId=72491&mediaType=VIDEO&as=5054&b=
>
> The largest bottleneck was the hard disk IO.  I would recommend that
> if the servers are somewhat active, you consider not assigning more
> than four guests per physical disk access (NO RAID MULTI-ACCESS, or
> divide this figure).  I have a lot of experience with this, and
> actually, if you had 16 physical drives in RAID0, that would be ideal!
>  Then you could run 64 guests simultaneously on one host -- which is
> the maximum VMware Server allows :-)

Of course, putting 16 drives in a RAID0 array is an insanely bad  
idea, due to the high probability of drive failure and the data loss  
on all 64 guests... I certainly wouldn't call it ideal, anyhow... :)  
I'm a big fan of RAID6 these days.

As for xen... I'd not touch it outside of an implementation with long- 
term support (i.e., RHEL5 or SLES10, not sure if Ubuntu 6.06 LTS has  
xen or not), where you have something of an assurance that updating  
your host OS isn't going to make your guests asplode...

-- 
Jarod Wilson
jarod-ajLrJawYSntWk0Htik3J/w at public.gmane.org