Cloudmin backup of Windows VPS

Submitted by pablofm on Fri, 06/18/2010 - 16:58

Hi Jamie,

I finally got around to installing a Windows VPS and have added it to Cloudmin as a managed instance.

I also added it as one of the system that I would like to be backed up. However, the backup is failing. Here's a copy of the log:

Backing up winweb01.domain.net  to /backups/vps/xen/winweb01.domain.net.tar.gz on Cloudmin master ..
   Creating LVM snapshots for disks of winweb01.domain.net ..
   Creating copy of LVM disk for winweb01.domain.net ..
   Removing LVM snapshots for disks of winweb01.domain.net ..
.. backup failed : Failed to create copy of LVM disk /dev/VolGroup00/winweb01_cloudmin_snap : dd: writing `/tmp/.webmin/777046_1_fastrpc.cgi/winweb01': No space left on device
200096+0 records in
200095+0 records out
6556741632 bytes (6.6 GB) copied, 178.924 seconds, 36.6 MB/s

I am not sure what the problem is, but I suspect it has something do with the fact that it's an NTFS file system and so your new backup scheme is not working and it's trying to make a full local copy of the logical volume before copying. It would be great if you could look into it.

Thank you.

Status: 
Closed (fixed)

Comments

Submitted by JamieCameron on Fri, 06/18/2010 - 17:06

Actually, it looks like the filesystem containing /tmp doesn't have enough free space. If your Xen instance on LVM has more than 1 disk, Cloudmin needs to copy those disks to temp files before backing up, as there is no way to create a single archive file from multiple LVs.

Does this Xen instance have multiple disks?

Can you increase the free space on the /tmp filesystem?

Submitted by pablofm on Fri, 06/18/2010 - 17:07

Hi Jamie,

No, I don't have more room. As a matter of fact, if you remember, I was the one that opened a ticket about the space issue before, which prompted you to change the way single disk instances are backed up. Do you remember?

Thanks.

Submitted by pablofm on Fri, 06/18/2010 - 17:09

Oh wait, the instance has the Windows CD image mounted on it by default. So it does have multiple disk images... Darn, that must be it.

Why is it that multiple disk instances cannot use the new backup scheme?

Thanks.

Submitted by pablofm on Fri, 06/18/2010 - 17:24

Not sure if this is related, but I just tried to use the Manage Disks tool for the windows instance and I get the following error:

Error - Perl execution failed

Undefined subroutine &server_manager::describe_disk called at /usr/libexec/webmin/server-manager/list_disks.cgi line 40.

Is there something missing in my installation of Cloudmin?

Submitted by JamieCameron on Sat, 06/19/2010 - 00:50

That error about describe_disk is odd, as that function definitely exists.

Does it go away if you SSH in as root and run /etc/webmin/restart ?

The reason that a multi-disk system cannot be backed up without first duplicating the disk images to files is that tar does not have a way to add a file to an archive from standard input. So the only way to create a backup tar.gz file of multiple disks is to copy each to a local file first, and then tar them all up :-(

Submitted by pablofm on Sat, 06/19/2010 - 09:54

Restarting webmin did the trick. I no longer get those errors.

Regarding backups, I am going to have to look at an alternative way of running backups. My VM's can be up to 320GB in size. I just cannot have that much space sitting in my tmp folder for nothing other than backups.

The solution for the single disk VM's was perfect, but on the off-chance that a 2 or more disk VM is required, I will be stuck. I need to think about this further. There must be a way...

I think that an agent-based backup solution is what is required. Anyhow, thanks for looking into it. If you have any ideas I would surely appreciate hearing them.

Thanks, Pablo

Submitted by JamieCameron on Sat, 06/19/2010 - 16:01

The only true solution would be for Cloudmin to change it's backup format to possibly use multiple files (one per disk).

Submitted by pablofm on Sat, 06/19/2010 - 19:16

Jamie,

That sounds like a viable option to me... :-)

How about a folder per server, and inside a tar.gz per disk?

You thinking about doing it? please ;-0

Thanks!

Submitted by JamieCameron on Sat, 06/19/2010 - 19:27

I've added it to my TODO list..

Submitted by JamieCameron on Wed, 08/31/2011 - 00:27

The next Cloudmin release will use a separate file per disk, and no temp space on the host system.

Submitted by Issues on Wed, 09/14/2011 - 01:22

Automatically closed -- issue fixed for 2 weeks with no activity.