Error Backing up Linux VM

[jorgene]

Hi,

Case ID: 00170647

I recently migrated a Linux VM to a W2012 (stand alone) Hyper-V server.
Now every backup job i run i get: Error: Client error: ChannelError: ConnectionReset
Network traffic verification detected no corrupted blocks

Tried to disable CBT, make new job's, reinstall Veeam Services @ Hyper-V host, other 2008 VMS on the same host there i no problem backup.

Any hit's of where to look for more info of what's goes wrong? I hade no troubble backing the Linux VM when it was installed on a W2008R2 Hyper-V host.

[Vitaliy S.]

Hi Jorgen,

Is this the only Linux VM that you have troubles while backing it up? Do you have a copy of this VM left on a Hyper-V 2008R2 host by any chance?

Thanks!

[jorgene]

Hi, Since it's a production VM it's was removed from the W2008R2 Hyper-V host when we migrated it to W2012 Hyper-V host and was successfully started there. But i noticed one thing, suddenly the VM was paused, with the "Insufficient disk space error message", even though there are plenty of space available(614GB), i have tried run multiple jobs against that VM and Another W2008R2 VM on the same host and i don't know which job that made it pause, but i suspect KB2791729 might be the issue here, maybe it's that whats causing the problem backing up the Linux VM to?

I have the possibility to restore the Linux VM back to the W2008R2 host (older copy) but i can't make it run on the network if i do that.

[jorgene]

Hi again, FYI. Now i noticed Another strange thing, the original VHD file was about ~12GB in size, now suddenly the *.vhdx file is 45GB large (it can grov to 140GB max, dynamically expanding disk). Now i have no ROOT accesss the VM because it's a branded NCentral VM, i do however have access to a management GUI and the disk info looks like this:
Filesystem Size Used Avail Use% Mounted on
/dev/hda2 109G 2.2G 101G 3% /
/dev/hda5 4.8G 462M 4.1G 11% /var/log
/dev/hda3 21G 2.9G 17G 15% /backup
/dev/hda1 122M 12M 104M 11% /boot
tmpfs 2.5G 0 2.5G 0% /dev/shm

Something caused the vhdx file to grov very much, but nothing in the VM seem to take up space, i'm not familiar with how Hyper-V backup integrates with Linux (it's a Cent OS), are there some "temp" data created during backup's which are not removed correctly?
(Maybe it's using the old W2008R2 integration services components? i will talk to support @ NCentral and see if they can install Linux Integration Services V3.3 For Hyper-V those should support W2012 Hyper-V)

[jorgene]

Correction: Linux Integration Services Version 3.4 for Hyper-V should support W2012 Hyper-V.
The following features are not available in this version of Linux Integration Services:
Integration services: Volume Snapshot Backup
Networking: TCP Offload

So, will i have to wait until 3.5 (if Volume Snapshot Backup are supported then) or will Veeam support backup of a Linux VM in W2012 with paused mode or something?
Anyone tested backing up a Linux VM in W2012 Hyper-V?

[Vitaliy S.]

But i noticed one thing, suddenly the VM was paused, with the "Insufficient disk space error message", even though there are plenty of space available(614GB)

Do have any related error messages in the Windows Event Log?

Now i noticed Another strange thing, the original VHD file was about ~12GB in size, now suddenly the *.vhdx file is 45GB large (it can grov to 140GB max, dynamically expanding disk).

Try to shrink your VHDX file as it is described in the following article, might help you to reclaim the disk space: Working with and resizing Windows Server 2012 VHDs

or will Veeam support backup of a Linux VM in W2012 with paused mode or something?

Actually we haven't observed any issues with backing up Linux VMs on a Hyper-V host. Can you please take a look at your job settings (Storage -> Advanced -> Hyper-V) and check whether you have this checkbox enabled -> "Take crash consistent backup instead of suspending VM"?

[jorgene]

I have tried all available settings, no success.

I do however observe that the Veeam Agent Crashes at the end of the backup job on the Veeam B&R server, when 1-2% are left of the job. But i suspect it's the current incompatible Linux integration services that's making all this problems.
I will wait until N-able releases Linux Integration Services 3.4 for the VM and then continue my investigation. But it might be interesting for you guys to look into why the agent crashes on the B&R side.

[Vitaliy S.]

Yes, we'll be glad to investigate this issue for you. Can you please upload the latest logs to our support team and give a reference to this thread?

[jorgene]

Evgeniya Pashentseva which is handling my case is out of the office and will be back on saturday.
There should be logs attached to Case ID: 00170647

We were unsuccessful in creating user mode crash dump log files in W2012 i tried editing the registry but it doesnt create any dump files, so maybe this differs in W2012?

[Vitaliy S.]

Well... if you had Veeam agents crashed, then all necessary log files should have been already created. Not sure whether user mode crash dump log will help.

[veremin]

FYI, there is a new memory dump option introduced in Windows 8 and Windows Server 2012 called “Automatic memory dump.” Thereby, it’s unlikely that old registry keys will work in the Win-2012 environment.

More information regarding this technology can be found in this article.

Hope this helps.
Thanks.