[nSLUG] vmware for Linux virtualization on production servers

George N. White III gnwiii at gmail.com
Thu Mar 12 17:43:34 ADT 2009


On Thu, Mar 12, 2009 at 3:33 PM, D G Teed <donald.teed at gmail.com> wrote:

> The powers of wisdom at my workplace feel our
> future should be run by vmware.  Blades or no blades
> that is what the powers of wisdom want.

Certainly many large organizations end up with a bunch
of servers, some running a very light workload, and can
consolidate the servers onto VM's running on one
machine.

> My experience with vmware has been limited to
> workstation, and I've seen cases where the
> virtual machine files become corrupt.  One
> way this happened was if the host was shutdown
> or powered off without the guest stopping properly.

Yes, but if you have a recent snapshot of the VM you
can be back up quickly even if you have to replace the
hardware.   You can design a system where the VM
is relatively static and databases are on a reliable mass
storage facility.

> You can't boot a vmware file from CDROM AFAIK,
> so how can it be fixed?  Doesn't seem to have
> the benefits of journaling or this wouldn't be happening.
>
> Does anyone have praise or horror stories about vmware?
>
> If it were up to me, we would be evaluating KVM. Redhat
> has announced they are dropping Xen and going
> 100% KVM.  Seems cleaner - a mere module to load.

Some education of managers is needed:

1.  not all workloads are equally suited to VM.  It may
    help to examine the suitability of existing servers
    for VM conversion.  Doing the exercise can identify
    candidates for early conversion but will also help
    educate managers.
2.  there are multiple VM offerings, which need to be
    explored to find best fit for your workload.  A server
    that is a poor fit for VMware may be better suited
    to KVM
3.  VM's are part of a system that has to include
    things like recovery from hardware failures.  Again,
    some applications (those serving static web pages)
    win because you can restore them quickly, others
    do not.

-- 
George N. White III <aa056 at chebucto.ns.ca>
Head of St. Margarets Bay, Nova Scotia



More information about the nSLUG mailing list