Problems excluding RDM

[donikatz]

I'm trying to exclude an RDM disk (physical mode) from a VM. This disk is 0:2, so I've setup the job to only backup 0:0, 0:1. However, I'm getting the following failure error:

Retrieving file list VCB error: Error: Other error encountered: Snapshot creation failed: The managed object of type "vim.VirtualMachine" identified by the MoRef "vm-12186" could not be found. An error occurred, cleaning up...

The other VMs in the job backup fine (none of them have a third disk). vcbvmname shows moref :32 for the VM, so I'm not sure to what the error is referring.

Thanks

[Gostev]

Hello, I am not sure either. Also, looking at the error my initial reaction was that it could be unrelated to disk exclusion at all. Looks like VI cannot find a virtual machine using the provided refID. Anyway, just guessing at this point - please send all logs from Help | Support Information to support@veeam.com and our support staff will engage developers to investigate this.

[donikatz]

Ok, will do. I was thinking the same thing about it not being related, but unfortunately without excluding it fails for obvious reasons, so no way to test around it without removing the disk, but this is a production server. So let's see what the logs tell you -- thanks!

[ssimakov]

donikatz, are you basically saying you see another error when not excluding RDM?

[donikatz]

well yes-- if you don't exclude the RDM, you receive an error that it can't take a sanpshot because of it. that's expected; VCB doesn't work with RDM, hence the exclusion. i'm in the midst of a back-and-forth with support, so will post back when we've narrowed it down. thanks

[ecleppe]

What version of VCB do you use? What's RDM pointing to? Fibrechannel or iSCSI?

[donikatz]

VCB 1.5, FC RDM. is there a difference related to exclusion?

[donikatz]

Update: Didn't resolve the errors -- support is still working on it -- but I decided to just change the RDM mode from physical to virtual for at least the time being. As we know, virtual mode can be backed up with VCB snapshots, no exclusion necessary. That's all for now... Thanks

[Gostev]

donikatz, what is your support case number - I would like to take a look at the progress.

[donikatz]

Ticket# 505386 -- Thanks

[Gostev]

Doni, I just did some research on this and looks like the issue is due to VMWare snapshots not working for guests with pRDM disks attached. While we can exclude disks from actual backup, VMware does not provide ways of excluding disk from snapshots (whole VM is always snapshoted, and this operation fails due to pRDM presence). Sounds like switching to vRDM is the only available option here unfortunately.

[donikatz]

makes sense, thanks for the update.

[davegold]

Have there been any changes in the vStorage API in the last 18 months that would allow pRDMs to be skipped?

[Gostev]

This does not have to deal with vStorage API features at all, but rather ability to create VM snapshot, which is essential for backup of running VM. If you are able to snapshot your VM manually using vSphere Client, then backup for this VM will work fine as well. Thanks!

[nehalem]

User guide page .26
Hardware
All types and versions of virtual hardware are supported, except physical RDM (raw device mapping) and Independent disks.
You can use disk exclusion functionality to exclude some of the unsupported disks from backup.
MBR disk partition table is required for file-level restore, GPT disks are not supported.

So how can Veeam backup exclude the pRDMs on backup Job while it uses Snapshot mechanism and VMware claims about pRDMs the following..

You cannot create a snapshot of a Physical Compatibility Mode RDM.
VCB cannot backup a RDM in Physical Compatibility mode.
VMware Data Recovery cannot backup a RDM in Physical Compatibility mode.

[Gostev]

You can use disk exclusion functionality to exclude some of the unsupported disks from backup.

Actually, unsupported disk exclusion happens automatically in v5 (new feature, documented in What's New). I need to tell technical writers to update the User Guide...

So how can Veeam backup exclude the pRDMs on backup Job while it uses Snapshot mechanism and VMware claims about pRDMs the following..
You cannot create a snapshot of a Physical Compatibility Mode RDM.
VCB cannot backup a RDM in Physical Compatibility mode.
VMware Data Recovery cannot backup a RDM in Physical Compatibility mode.

OK, so in your opinion, what exactly from this list could restrict Veeam Backup from taking VM snapshot, and then backing up all VM disks but pRDM?

[davegold]

Hi,
I'm not getting it. Let me try with a different question.

If I have a VM that has one VMFS disk (OS and application install) and one physical mode RDM, can I use Veeam to back up the VMFS only?

Previous posts have indicated that the vStorage API doesn't allow one to do a snapshot of just the VMFS, whereas VCB tended to fail more gracefully.

Thanks,

Dave

[Gostev]

If I have a VM that has one VMFS disk (OS and application install) and one physical mode RDM, can I use Veeam to back up the VMFS only?

Yes, absolutely you can.

Previous posts have indicated that the vStorage API doesn't allow one to do a snapshot of just the VMFS, whereas VCB tended to fail more gracefully.

I believe you misread it. Reading back through my response yesterday, I said vStorage API has nothing to deal with ability to create snapshot. And please don't read above my yesterday's post to avoid confusion, keep in mind that you bumped 1.5 year old thread talking about entirely different platform which was VCB-based Veeam Backup 3 backing up VMware VI 3 at a time.

[davegold]

Good point. I should have opened a new conversation.

Thank you.

[alextan]

Hi all

We just upgraded the farm from 4.0 to 4.1. In the previous version we could backup the system disks of the cluster nodes, now we cannot any longer.

I have the same problem specified in this post but I cannot understand how to make it work.
I read some other posts like this

http://www.veeam.com/forums/viewtopic.php?f=2&t=2890

and i found out that under vSphere 4.1 the behaviour for VMs with RDM Physical C.M. has slightly changed.
But I also read that I can usr VCB Mode and excluded all the shared disks (only system disk selected)
Well, I tried, but I have always the same behaviour: No Snapshot is taken on the VMs, so the backup fails.
Also launching the vcbmounter cli by hand with "-m nbd" parameter is not working...
Where Am I wrong?

My env: Windows 2008 R2 Backup Proxy with VEEAM Backup 5 + VCB 1.5 U2
Vsphere 4.1 ESXi/ESX build 433742

Thanks
Alessandro

[foggy]

Alessandro, actually, physical RDMs are automatically excluded from a backup job in v5 so you do not need to exclude them manually or use VCB mode to back up. But the problem here might be in the fact that snapshotting of a Windows cluster VM with SCSI controllers engaged in bus-sharing is not supported by VMware.

What type of error do you get?

[alextan]

I'm using Vsphere Server 4.1.0 build 345043, esx 4.1.0 build 433742, Veeam Backup 5.0.2.230 and VCB Framework 1.5 U2
I also explicitly excluded the shared disk selecting just the system disks to be processed

This is the error shown in vCenter client
Create virtual machine snapshot
drwp10a
Virtual machine is configured to use a device that prevents
the snapshot operation: Device '' is a SCSI controller
engaged in bus-sharing.
View details...
Administrator
DRWI200.costa.it
30/08/2011 14:58:35
30/08/2011 14:58:35
30/08/2011 14:58:35

This is actually the output of Veem backup.
0 of 0 files processed

Total VM size: 10.00 GB
Processed size: 0.00 KB
Processing rate: 0 KB/s
Backup mode: VCB NBD
Start time: 8/30/2011 2:57:38 PM
End time: 8/30/2011 2:58:06 PM
Duration: 0:00:28


Waiting for VCB catalog
WaitForVCBCatalog failed
QueryCatalog failed
Client error: Vcb process is terminated
Waiting for catalog data has failed.Vcb process is terminated
Waiting for catalog data has failed.

Server error: End of file

Thank you in advance

[foggy]

Virtual machine is configured to use a device that prevents
the snapshot operation: Device '' is a SCSI controller
engaged in bus-sharing.

This is really it , as you can see..

[alextan]

yes,of course.. but I can see some posts earlier:

Yes, absolutely you can.

I understood that
-> the behaviour has changed from vsphere 4.0 to 4.1.
- Under 4.0 the snapshot is taken, and the RDM Physical CM are automatically excluded
- Under 4.1 the snapshot fails, no backup is taken, if you use vStorage API,
BUT... in this case if you use VCB ( or Veeam Backup in Legacy mode (VCB) you can still backup the system disk, that is what I want to do.

So what I tried is to use the legacy mode, also manually excluding the RDM... but i can't see any difference.

Have I understand wrongly? Can I still backup the system disk of a cluster node as I was doing with vSphere 4.0? If Yes, How?

Thanks

[Gostev]

Physical RDM = fine, bus sharing in addition to that = not (VMware snapshot limitation).

[alextan]

Thanks!
Finally I've got the point.

However this is a "bad new feature" of vSphere 4.1