Hi,

2012/5/7 Jonathan Bayer <[email protected]>:
> We are moving into the VM area, using KVM on Redhat 5/6 systems.
>
> Our VMs are a mix of disk image files, and LVM partitions.
>
> On thing I don't have yet is a good backup strategy for all the VMs
>
> The critical VMs are replicated using MySQL replication, but that's only a
> few.

I generally run bacula in the VMs, and use a reasonably-reliable
script that shuts them down for a minute, snapshots, boots them back
up.
I don't care that online snapshots are almost as good, nor that you
can freeze filesystems. The snapshot backup is only weekly and I can
take the ~60 minutes of yearly downtime incurred by that. :)

The backup script is run on the host, since I have control of them. It
could be done with sudo. Note this is for Xen i'm just including it so
you can see the general procedure.
https://bitbucket.org/darkfader/vmbackup/src/74dc64b5b5a4/backup_vm_offline_snapshot.sh

One could of course replace the shutdown with a xm snapshot or
something kvm-ish for your case.

My general idea is that I want the following three things at ready:
- cobbler to reinstall the OS disk
- bacula to do a full restore
- a script that can do a on-demand or weekly backup via lvm snapshot


I'll freely admit not all things are always performing / working as
I'd want it, but I've seen especially the combination is working very
robust now.
This is no longer my job, so I can't invest time even just weekly to
keep an eye on things, which is why i'm happy to see the bacula and
snapshot to work, and work, and work. (It gets a glance more often.
But still)

A problem has turned out to be in cobbler since I put the server in a
spot with too low bandwidth and the hosting software I am using
doesn't AT ALL consider a real OS install. I'm still wondering how I
can really shoe-horn cobbler installs into there. So OS install is a
major issue at the moment.
$plan is to move install and backup servers onto systems with very
good connectivity and then only replicate both backup and cobbler to
the old, slower location.
(I never again wanna see a xen host reinstall from cobbler to take 2
hours for 500MB!!!)

And, something I'd highly recommend and really dream off:
After doing the VM snapshot, convert it into an OVF image so that it
can immediately imported into virtualbox or VMWare.
The OVF toolset is really complicated though, I have avoided going
back to that endeavour since December.


If you don't have access to the hosts, many many of the options die.
Then I'd go with "automated OS install" plus "full backup" again.
As already said, replication doesn't count there :)

Last, where your backup goes mostly depends on your recovery times
(RPO or also storage wall are good buzzwords here). A close-by backup
server with a raid6 of 2.5" 1tb laptop sata disks beats pretty much
anything for restore speed with VM images, and nobody stops you from
running a second independent backup to a wan location (i.e. the cloud)

I hope this wasn't too confusing and instead gave some ideas :)

Greetings,
Florian
_______________________________________________
Discuss mailing list
[email protected]
https://lists.lopsa.org/cgi-bin/mailman/listinfo/discuss
This list provided by the League of Professional System Administrators
 http://lopsa.org/

Reply via email to