cloudstack-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Julien Garet <>
Subject Re: backup a cloudstack deployment
Date Wed, 24 Oct 2012 22:22:25 GMT

> De: "Paco Orozco" <>
> À:
> Envoyé: Mardi 23 Octobre 2012 08:22:29
> Objet: Re: backup a cloudstack deployment

> Hi Julien,

> Good point! We have a private IaaS cloud and we have the same
> question.
> At the beginning documentation and forums recommends to backup MySQL
> DB
> and the secondary storage.

> I'm using Cloudstack and Xen servers with LVM as a primary storage.
I'm using KVM along with Cloudstack with iSCSI and GFS2 (on Dell Equallogic) as primary storage.

As secondary storage, I am thinking at using disk based backup appliance with inline deduplication
(Quantum, EMC DataDomain, ...), has anyone tried such a setup ? Are performances good enough
or do I need some kind of speedy NFS server ? 

> I'm doing it but I've got some not solved questions.

> 1) Geoff says "You should have every VM running a Scheduled Snapshot
> routine, that way if you have a disaster, you can recreate your
> architecture, and restore VMs from Snapshots / Templates". When you
> schedule this snapshot routine it will create snaps on secondary
> storage. Does this snaps count as a consumed resources for users?
> Must
> they will pay for it? Can users delete them?
As far as I know, a snapshot is a resource as others, it has its own limits, different from
the volumes. Users can delete their own snapshots. The service offer we are planning to provide
is to tell users they have all the tools to plan their own backup (via the snapshots) and
are responsible to set it up for their VMs. We ensure that in case of disaster on primary
storage, they will have tools to recover failed VMs. 

I've done some testing around snapshots (manual or scheduled) and it appears that, vm running
or not, I have a lot of errors. For example, I've scheduled hourly snapshots on a VM, keeping
the last 3, and I currently have : the last backup is in error, the two others are OK on the
root disk, and for the data disk only the last is good. 

Does anyone face this kind of snapshots problems ? 
Another question around that, are there means to have a copy of a volume on secondary storage
or only snapshots are stored on it ? 

> 2) I'm now testing a solution for PHD in order to do VM backups from
> Xen
> Server. Are you using Xen or KVM/VMware?
I did not look for kvm specific backup solutions, I have a little background with XenServer
and last time I looked at it, I finished with a perl script that did vm snapshoting before
moving the volume to a dedup appliance (Quantum DXi) 
> 3) I need to protect myself from harware failures (mirroring) and
> software or human errors (backup). Are you only using mirror?
For human errors, in Cloudstack, I think that the cleanup delay before removing destroyed
VMs can help a lot. I'm also quite afraid of data corruption on the raid array, e.g. many
disks failing at the same time because of a bad series... How long will it take to recover
the whole platform if only from secondary storage ? And recover will only be on the user behalf

How will Cloudstack behave if a lot of VMs on a primary storage are not available ? 

> Thanks
> --
> Paco Orozco (
> SIP:
> Backoffice. Àrea de Serveis TIC
> UPCNet
> Edifici Vértex - Pl. Eusebi Güell, 6
> Teléfon centraleta: 93.40.11600
> GPG Key ID: 0x3EDEC0AC

  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message