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PTT_Admin's avatar
PTT_Admin
Level 2
13 years ago

Exchange DAG backup failing status 156, after moving Mail DB to iSCSI LUN

We have a couple of Windows 2008 R2 servers running Exchange 2010 in a DAG configuration.

We have been backing them up with Netbackup 7.0 without issue, until we moved one of the Public folder DB's to an iSCSI attached LUN.

Now, that DB fails to backup, while the others continue to succeed, as part of the overall DAG backup.

Sample of failure:

4/20/2012 9:21:26 AM - begin Create Snapshot
4/20/2012 9:55:16 AM - Critical bpbrm(pid=680) from client MAILSERVER: FTL - snapshot preparation failed, status 156  
4/20/2012 9:55:16 AM - Warning bpbrm(pid=680) from client MAILSERVER WRN - NEW_STREAM0 is not frozen   
4/20/2012 9:55:16 AM - Warning bpbrm(pid=680) from client MAILSERVER: WRN - Microsoft Information Store:\Public Folder Database is not frozen
4/20/2012 9:55:18 AM - end Create Snapshot; elapsed time: 00:33:52
4/20/2012 9:55:25 AM - end writing
Status 156

I've looked through the info I could find online, and find more articles relating this issue with VMware backups. Can anyone tell me why moving the DB to an iSCSI LUN has created this issue?

Thanks

7.1.x and Earlier
Agent for Microsoft Exchange Server
Backing Up
Backup and Recovery
MS Exchange
NetBackup
VMware
Windows

3 Replies

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  • Marianne's avatar
    Marianne
    Level 6
    13 years ago

    If you Google "VSS snapshot with iSCSI lun", it seems that Microsoft VSS has a problem with iSCSI luns (not NBU).

  • PTT_Admin's avatar
    PTT_Admin
    Level 2
    13 years ago

    Thanks Marrianne

    My search results (based on your suggestion) were more related to Windows Server 2003 and the older versions of the Microsoft iSCSI initiator software.

    My Exchange 2010 servers are 2008 R2, running version 6.1 build 7600 of the iSCSI initiator software.  There is no update beyond that I can find.

    According to technet VSS should work with iSCSI:

    "From the guest operating system, you can connect directly to iSCSI LUNs on a storage array. Direct connectivity using iSCSI offers the following advantages over other iSCSI LUN options:

    • You can transparently operate SAN management applications.
    • Supports guest clustering.
    • You can connect to iSCSI LUNs without shutting down and restarting the guest operating system.
    • You can manage LUNs in the guest operating system in the same way that LUNs are managed in the physical environment.
    • Support for VSS hardware snapshots in the guest operating system."

    Also, I am not seeing any errors in the Windows event logs.  I would assume if the issue was with Windows and VSS, there would be errors associated with each attempt.

    As well, I am running SMVI backups of this Exchange VM without issue.  The default action is to take a quiesced snapshot which should also be calling the VSS writer. These backups run fine (and at a different time), so I'm really not finding any evidence that the issue resides within Microsoft VSS and compatibility with iSCSI attached storage.

    That said I'm perfectly willing to accept that fact that is the issue, if someone could provide me with data specific to my situation that proves the case.

  • V4's avatar
    V4
    Level 6
    13 years ago

    PF backups are not considered under DAG . DAG is for User Mailbox Database. Create Seperate policy for Public folder and check if it helps

    Also is service pack 1 or 2 applied on Exchange ??

    Go to Member server where PF is mounted

    Create bpfis log directory under netbackup\log

    and open Backup Archive and restore GUI (run as administrator)

    increase logging level to max from troubleshooting tab

    recycle NBU client service

    and start the job.

    post the detailed job detailed along with bpfis logs which must have generated.

    What are VSS writer status ???? Do you see anything suspicious in event viewer