WOFB recommendations - Veritas Net Backup

This is a discussion on WOFB recommendations - Veritas Net Backup ; We are running NetBackup V5.1. It is a new installation and I am trying to figure out how the open file backup is working. We've had a couple of machines run out of disk space with the huge cache files ...

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Thread: WOFB recommendations

  1. WOFB recommendations


    We are running NetBackup V5.1. It is a new installation and I am trying to
    figure out how the open file backup is working. We've had a couple of machines
    run out of disk space with the huge cache files created by the open file
    manager running. We've turned it off for a couple of clients because of
    problems like that. Questions:
    1) Can you turn it off globally rather than one client at a time?
    2) What is the biggest drawback or potential problem with turning it off?
    Thanks.
    Paul

  2. Re: WOFB recommendations

    Hi Paul,

    To answer your questions ;
    1) I don't think it can be turned off globally, it's a per client setting -
    but I may be wrong. Can anyone else confirm if there's a setting (hidden or
    not)?
    2) At the risk of sounding obvious - If you turn VSP off you may have locked
    files that do not get backed up.


    Now for my spiel...

    I assume that you are running on Windows. I also assume that you are using
    VSP, and that OTM is not available. If your client was previously a v4.5
    client, and has been upgraded to v5.1 then OTM should still be available.
    If your clients are fresh v5.1 installs then OTM will not be available. OTM
    requires a licence on your master server. OTM was the open file handler
    before VSP. OTM is not avauilable on v6.0 clients. OTM has different
    parameters that can also be tuned, similar to VSP, but different.

    I would experiment with your problemattic clients. Not all clients have
    problems with locked files, so some clients don't need VSP at all. What I
    mean is, that you may be using VSP on clients that don't need it. The proof
    of the backup is did it finish with a status 0. It's taken me a long time
    to eradicate status 1 completions from my backups, and I still have a few
    that crop up from time to time.

    Make sure that you are not scanning any live database files (e.g. Oracle,
    SQL, Sybase, Domino), as it is best to take these files using separate
    special agents/policies. At our site we don't even use the Oracle agents,
    although we do use the Domino and MS SQL agents. Our Oracle DBA's prefer to
    export their databases, and then our clients run to take the copy, and we
    explicitly exclude the live database folders.

    You should aim not to have any "status 1" backups. You are looking to
    always achieve "status 0". Maybe there are certain files that do not need
    to be secured. Talk to your application owners to see what can be done. We
    have a few files with some apps, and after discussing with the system owners
    we've found that most of the locked files were just that - temporary lock
    management files that do not need to be backed up - so we simply exclude
    them. Always check first though. You don't want to exclude a critical file
    that requires some other solution.

    In the client properties you can specify which drives can and can't be used
    to store the VSP cache file. I believe that it's a common problem to be
    left with VSP cache files until you tune it properly. You can do this by
    adjusting how much free space NetBackup VSP can use.

    Note that it can sometimes require a reboot to remove the old cached files.
    They get left behind sometimes because the NetBackup client software has
    crashed or run out of space because you haven't tuned the VSP settings.
    Sometimes a reboot will automatically remove the old VSP files for you, but
    sometimes it won't, so sometimes you have to reboot and then remove them
    manually. This was a problem for us too with v5.1. You'll be glad to know
    that the v6.0 client does a much better job of ensuring that they don't get
    left behind. In v6.0 the NetBackup client, creates a special
    \NBU_VSP_CACHE\ folder on the root of each drive, and I guess this allows
    the locking mechanism to handle problems a lot better.

    It is worth checking how much free space is available on each drive, and
    tuning your VSP settings accordingly.

    Remember, VSP waits for the system to quiesce (i.e. waits for a quiet
    moment, a minimum period of 5 minutes with little or no disk activity), so
    that it can start VSP. We tend to specify C: in the exclude list for VSP,
    for clients that have more than one drive. This doesn't mean do not use VSP
    on the C: drive, it means do not store any VSP cache files on the C: drive.
    Normally the C: drive is very busy, and you definitely do NOT want this
    drive to fill up with VSP cache files, so there's not a lot of point writing
    a large write cache file to a busy disk, it just slows the machione and
    backup down. Of course this doesn't help VSP during it's wait for a quiet
    moment.

    Before you complain about VSP, you must remember that NBU is an enterprise
    product. VSP works out of the box on most clients, but we all have some
    upon which it doesn't. If most of your clients are a mess with disks that
    are nearly full, then you're going to have a problem with most of your
    clients. Also, remember that it's a general recommendation that no NTFS
    disk ever go beyond 70% used space.

    Tuning VSP is your key to success.

    Regards,
    Dave.



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