[CentOS-virt] Slightly OT: Centos KVM Host/Guest functions and LVM considerations

Fri Sep 16 20:46:27 UTC 2011
Eric Shubert <ejs at shubes.net>

On 09/16/2011 01:10 PM, Ed Heron wrote:
>    I've been considering this type of setup for a distributed
> virtualization setup.  I have several small locations and we would be
> more comfortable having a host in each.
>    I was nervous about running the firewall as a virtual machine, though
> if nobody screams bloody murder, I'll start exploring it further as it
> could reduce machine count at each location by 2 (backup fw).

I've been running IPCop as a VM for a few years now. Works like a charm. 
You can set up VPNs between IPCop VMs as well if you like, effectively 
bridging LANs at each location. Just be sure that subnets are distinct 
at each location.

I like less hardware. Fewer points of failure means more reliability 
(with the exception of redundant parts of course) as well as cost savings.

>    I'm not as paranoid about the host providing storage to the VM's
> directly, for booting.

There might be a good reason for doing so that hasn't occurred to me.
I wouldn't lose much sleep over it. Whatever works. ;)

>    I'm considering using DRBD to replicate storage on 2 identical hosts
> to allow fail-over in the case of a host hardware failure.

A fine idea, if you can swing it. To be honest though, with the HDDs on 
raid-1, the likelihood of failure is rather small. Depending on your 
cost of down time, it might do just as well to have spare parts (or a 
spare machine) standing by cold. Depends on the business need though. I 
do like having spare hardware at hand in any case.

>    What kind of VM management tool do you use; VMM or something else?

As I said, I've been using VMware Server up to this point, so I've been 
using that web interface primarily, with cli configuration editing where 

As I'll be migrating to KDE/CentOS very soon, does anyone have 
recommendations? TIA.

-Eric 'shubes'