Video Screencast Help
Symantec to Separate Into Two Focused, Industry-Leading Technology Companies. Learn more.

NetBackup 7.5 & VMware BLIB

Created: 01 Feb 2013 • Updated: 06 Feb 2013 | 5 comments
This issue has been solved. See solution.

Although I know that there is a lot of information about BLIB out there, I've had some conflicting advice from people at Symantec and I've found myself feeling unsure about certain facts regarding it. Apologies if this is covering old ground, but I've got a handful of quick questions that I'd like to confirm before I look into implementing it in our environment (NBU 7.5.0.4).

  1. Am I right in thinking that changed block tracking does need to be enabled on the VM as well as BLIB in the policy, and that enabling it on the VM requires it to be powered off?
  2. If BLIB is enabled, can I still do normal granular file restores from my VMware backups if I'm doing a mapped backup/"file recovery from VM backup" is ticked?
  3. Will BLIB enable me to do incremental restores to a VM without requiring the NetBackup client and a network connection?
  4. I've read that a full backup of a VM with BLIB enabled only backs up blocks that have changed since the .vmdk file was created - does this have consequences when restoring the entire VM?
  5. What are the version requirements on the VMware side of things when using BLIB in NBU 7.5?

Thanks in advance.

Comments 5 CommentsJump to latest comment

Yasuhisa Ishikawa's picture

Am I right in thinking that changed block tracking does need to be enabled on the VM as well as BLIB in the policy, and that enabling it on the VM requires it to be powered off?

CBT and BLIB is not prerequisite to VM full backups, but both should be enabled for storage space saving by incremental backups. You need to power off the VM when enabling CBT.

If BLIB is enabled, can I still do normal granular file restores from my VMware backups if I'm doing a mapped backup/"file recovery from VM backup" is ticked?

Yes if you configured the policy with "Mapped full VM backup"(before 7.5) or "Enable file recovery from VM backup"(7.5 or later).

Will BLIB enable me to do incremental restores to a VM without requiring the NetBackup client and a network connection?

Well, if what you mean is file level restore - no. To restore files to VMs directly, NetBackup Client must be installed on VMs.

I've read that a full backup of a VM with BLIB enabled only backs up blocks that have changed since the .vmdk file was created - does this have consequences when restoring the entire VM?
I think you have confused with "full backup of a VM with CBT enabled". State in "Using VMware's Changed Block Tracking for full backups only" in guide is similar.
Taking chaged blocks from initial is enough for full backups, and there are no consequency for VM recovery, I think.
 
What are the version requirements on the VMware side of things when using BLIB in NBU 7.5?
VMware and VM version  must be supported version. Requirments are described in compatibility.
http://www.symantec.com/docs/TECH127089

Authorized Symantec Consultant(ASC) Data Protection in Tokyo, Japan

Shaun Taylor's picture

Thank you for your reply - really helpful.

Will BLIB enable me to do incremental restores to a VM without requiring the NetBackup client and a network connection?

Well, if what you mean is file level restore - no. To restore files to VMs directly, NetBackup Client must be installed on VMs.

I was wondering if it's possible to do an incremental virtual machine restore, similar to restoring the entire VM / .vmdk files from a full backup.

VMware and VM version must be supported version. Requirments are described in compatibility.
 
Looking into this a bit further, I found the following technote which suggests that BLIB will only work with vmx-07 VMs and later: http://www.symantec.com/docs/TECH182133. I couldn't find any reference to this in the document that you linked to in your above post. Is this still the case? I am currently backing up vmx-04 VMs successfully with NBU 7.5.0.4, although I haven't moved my policies from Flashbackup-Windows to VMware yet so I'm not sure if I'll hit problems with vmx-04 VMs then.
Tomer Gurantz's picture

From the Symantec NetBackup for VMware Administrator's Guide:

"For the restore, the virtual machine's hardware version (such as 7) is later than the hardware
version that the target server supports. If VMware Tools cannot convert the virtual machine's
hardware version to an earlier version, the restore fails."
 
So, I don't think that it's saying that vmx-07 is a necessity per se, but that depends on the rest of your VM infrastructure and versions.

Senior Principal Technical Education Consultant with Symantec Corporation

Yasuhisa Ishikawa's picture

I was wondering if it's possible to do an incremental virtual machine restore, similar to restoring the entire VM / .vmdk files from a full backup.

VM recovery from incremental backups does not require NetBackup client on source VM. Destination VM is created in process of recovery, so requirements on destination VM is not matter.

Please note that you need to enable BLIB to recover VM from incrementals. You can not recover VM from incremental backups without BLIB. Without BLIB, only file level restore is possible from incrementals.

Looking into this a bit further, I found the following technote which suggests that BLIB will only work with vmx-07 VMs and later: http://www.symantec.com/docs/TECH182133. I couldn't find any reference to this in the document that you linked to in your above post. Is this still the case? I am currently backing up vmx-04 VMs successfully with NBU 7.5.0.4, although I haven't moved my policies from Flashbackup-Windows to VMware yet so I'm not sure if I'll hit problems with vmx-04 VMs then.

Sorry, compatibility document does not mention to VM version.
Following statement exist in NetBackup 7.5 for VMware Administrator's Guide. VM version must be vmx-07 or later.

Note the following about block level incremental backups:

  • Works only with ESX 4.0 or later virtual machines at version vmx-07 or later.

  • Requires vStorage (cannot be used in VCB-based backups). 

In general, this sort of requirements is came from some technical reason, so it is hard to think vmx-04 become supported. In this case, please have a look at http://www.symantec.com/docs/HOWTO44451. BLIB requires CBT, and CBT requires vmx-07 or later. vmx-04 does not support CBT, so you need to update your VM to vmx-07.

Full backup(and even incrementals) may end with status code 0, but it is possible that recovery from incrementals(and even full) may not work. Symantec does not ensure successful VM recovery in unsupported configuration.

Authorized Symantec Consultant(ASC) Data Protection in Tokyo, Japan

SOLUTION
Shaun Taylor's picture

Really appreciate all the replies, thanks for helping me to make sense of it. If enabling BLIB will allow me to recover VMs from incrementals then it definitely sounds like it'll be worth the work to implement BLIB and CBT in our VMware environment.