Lee Marzke on 11 Nov 2009 20:29:50 -0800

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Re: [PLUG] cheapass VM host platform?

Mike Sheinberg wrote:
> Anyone have any experience configuring (free) backups with ESXi 4?
> Currently I'm working for a company utilizing VMWare Server which
> really lacks a lot of the great features/performance I've seen in
> previous ESX versions (3.5). Many VMware users on forums recommend the
> 'ghettoVCB' script (following
> http://communities.vmware.com/docs/DOC-8760). Anyone have any
> experience with this method or have any other suggestions for do it
> yourself ESXi backups?
> Thanks!
> Mike

I was forced to use Vmware server for a year until I got funding for
VCenter/ESXi on 2 new DL-360 G5
hosts and a SAN.

The tradeoff, is that VCenter provides better use of RAM,  VM Templates,
thin provisioned disk that
don't severely fragment the NFTS file system,  and of course with
Enterprise edition you get Vmotion
and Storage Vmotion that allow you to move the machine to a new host, or
move the storage to
a new volume without shutting it down.

Since a VM move/copy may take 2 to 6 hours or more,  the Storage Vmotion
feature will save a lot
of downtime, as you can do that while the machine is running under light

For backup on Vmware Server I have some scripts that automate the
shutdown, copy,  zip, and restart
of the VM.   However in practice ( with 4 hosts and 12 VM's )  I found
that one or more scripts/backups
failed every day.  The VM's were down for 3 or 4 hours each for the
copy,  and we had to stagger
the copies.  A single backup would also tie up the Vmware Server host's
SATA disk so much that the
other VM's would be unresponsive.   If you want these scripts let me
know off-line.

So basically this strategy with moderate size VM ( 10 to 40G each ) just
didn't work in practice.

If you try to do the same using ghettoVCB I imaging the problems would
be similar.   Also just getting a
command line prompt on ESXi voids your warrentee and support.  On top of
that,  standard tools are not
available ( only busybox ) and important files ( even crontab ) are
overwritten at each boot - so anything
you configure is wiped out on reboot.

Yes, I've run some commands from ESXi command line,  but for instance
the ghettoVCB script is
mostly parsing text configuration files, and running commands

Sample portion of ghettoVCB:

for VM_NAME in `cat "${VM_INPUT}" | sed '/^$/d' | sed -e
        VM_ID=`grep -E "\"${VM_NAME}\"" /tmp/vms_list | awk -F ";"
'{print $1}' | sed 's/"//g'`

This depends on the config file text format of that version of ESX,  and
overall is a very fragile way
of controlling ESX.   I think you would have just as many problems with
this script
( and indeed the comments on the forums agree ) 

If your running development or production on these machines,  you really
should invest in VCenter
for all the advantages above. 

If you get the VMware Essentials Plus package,  it includes a supported
"Disaster Recovery" program
that will do what you want.     This includes VCenter,  gives you
template support,  and the DR program
for something like $2995 ( for up to 3 hosts with 2 CPU's each ,  and a
free copy of Vsphere Essentials
server, and the DR program )


So spending a week setting up ghettoVCB, and then futzing with it,  will
already cost
more than buying Essentials Plus.   Plus  you will have template support
to help manage
your VM rollouts.

Also,  I found that generally if you present the options to management
with costs and reliability explained it is
usually possible to get funding,  because it just make sense,  while
spending a week of your time to
get an unreliable solution does not make sense.


"Between subtle shading and the absence of light lies the nuance of iqlusion..."  - Kryptos

Lee Marzke,  lee@marzke.net   http://marzke.net/lee/
IT Consultant, VMware, VCenter, SAN storage, infrastructure, SW CM
+1 800-393-5217  office         +1 484-348-2230               fax
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