Netware 4.2 data missing - Netware

This is a discussion on Netware 4.2 data missing - Netware ; We have a netware 4.2 compaq proliant server with ArcserveIT. The physical drive crashed and now we only have the mirrored drive. It doesn't show the last two months of files. We do daily back ups on a DAT for ...

+ Reply to Thread
Results 1 to 3 of 3

Thread: Netware 4.2 data missing

  1. Netware 4.2 data missing

    We have a netware 4.2 compaq proliant server with ArcserveIT. The physical
    drive crashed and now we only have the mirrored drive. It doesn't show the
    last two months of files. We do daily back ups on a DAT for one week. We
    kept getting broadcast messages that backups were successful but when I
    tried a backup the tapes had 0 data on them, presumably because it couldn't
    read the main drive. We never got a broadcast of a failed drive. When the
    mirrored drive takes over doesn't the server write files to it and the
    backup doesn't use the data from the mirrored drive or is the data hiding
    somewhere else?
    We would like to recover the last 2 months. Does anyone have any ideas?
    Thanks



  2. Re: Netware 4.2 data missing

    On Wed, 18 May 2005 04:59:05 -0500, Ron Young wrote:
    > We have a netware 4.2 compaq proliant server with ArcserveIT. The physical
    > drive crashed and now we only have the mirrored drive. It doesn't show the
    > last two months of files.


    Is this drive being mirrored by the hardware (the ProLiant supports this,
    if I recall correctly), or mirrored in software? The recovery is different,
    depending on what you're trying to use to recover. If you don't know, don't
    touch anything until you get somebody who does. You risk losing all of your
    data if you do this wrong.

    I'm puzzled by the comment that you're missing two months of files. How are
    you seeing this? I've seen plenty of disk failures, but none of them have
    managed to lose only new files.

    > We do daily back ups on a DAT for one week. We
    > kept getting broadcast messages that backups were successful but when I
    > tried a backup the tapes had 0 data on them, presumably because it couldn't
    > read the main drive.


    Well, that's one painful lesson learned. You have to actually check your
    backups, and it's important to occaisionally test them to make sure you
    can restore from them.

    It sounds like maybe you have a few things going on here. Whether these
    disks were mirrored in hardware, or software, whenever the one disk failed,
    all reads and writes should still have been going on on the other disk.
    What you're describing, that nobody has noticed for the last couple of
    months, but that suddenly all of their recent data is gone, sounds like
    maybe the mirror was actually broken a while ago, then the disk failed,
    and now you're back to an older version of everything via the formerly
    mirrored disk.

    > We never got a broadcast of a failed drive. When the
    > mirrored drive takes over doesn't the server write files to it and the
    > backup doesn't use the data from the mirrored drive or is the data hiding
    > somewhere else?


    Hardware mirroring treats the two disks as one as far as the operating
    system is concerned. Some drivers may report a disk failure to the OS, but
    you may have to have been running other monitoring software (Compaq
    included their Compaq Insight Manager SNMP monitoring software, and all
    of the support files needed for it to monitor your NetWare server) to
    have notification of hardware failures. Generally, when done in hardware,
    since the OS doesn't know that there has been a failure, it's up to the
    hardware to handle the failure and use whatever disk(s) are still working.

    Software mirroring treats the two disks as two disks, and the OS does
    the management of writing data to both. In the event of a disk failure,
    the OS does know about it, and will continue using the working half of
    the mirrored pair.

    > We would like to recover the last 2 months. Does anyone have any ideas?


    Lots of ideas, but you need to provide more hard information. I very much
    doubt that your data is hiding somewhere in the machine. Why it was lost
    is interesting, and may be helpful to know for figuring out your recovery
    plan.

    > This is a continuation of the first post. Evidently the physical drive
    > cratered so the server is running off the mirrored drive. Is that how it can
    > find the files to boot because I would think the C drive is gone.


    If you are doing hardware mirroring, then the hardware is taking care of
    this.

    > When I put
    > a new drive in I was going to format it with a dos partition, but if I make
    > it the C drive will I then lose my mirrored drive or will I then be able to
    > copy it over to my new drive. The current drive is called a logical drive
    > and there doesn't seem to be any way to unmirror it and make it my main C:/
    > drive.


    It sounds like you are _probably_ doing this via hardware mirroring. You need
    to find out for sure before you touch anything here. Do NOT procede with
    installing a new disk or formatting or partitioning or anything like that
    until you know exactly what you're doing.

    Best would be to make two good, verified, and complete backups of this system
    via different methods before continuing. One can be your tape system, if you
    can convince Arcserve to do it. The other one you could do via a simple file
    copy (if you don't care about file ownerships or rights), or use the native
    backup tool (sbackup, if I recall NW4.2 correctly).

    While that's running, research your configuration. Find out if you're working
    with hardware or software mirroring. If it's hardware, get the documentation
    on how to replace a failed disk correctly. If it's software, get familiar
    with the process of installing a new disk and putting the mirror back together.


    --
    | David Gersic www.zaccaria-pinball.com dgersic_@_niu.edu |
    | Real BASIC programmers girlfriends wear G$'s. |
    | Email address is munged to avoid spammers. Remove the underscores. |

  3. Re: Netware 4.2 data missing

    On Thu, 19 May 2005 17:34:12 +0000 (UTC), David Gersic
    wrote:

    >On Wed, 18 May 2005 04:59:05 -0500, Ron Young wrote:
    >> We have a netware 4.2 compaq proliant server with ArcserveIT. The physical
    >> drive crashed and now we only have the mirrored drive. It doesn't show the
    >> last two months of files.

    >
    >Is this drive being mirrored by the hardware (the ProLiant supports this,
    >if I recall correctly), or mirrored in software? The recovery is different,
    >depending on what you're trying to use to recover. If you don't know, don't
    >touch anything until you get somebody who does. You risk losing all of your
    >data if you do this wrong.
    >
    >I'm puzzled by the comment that you're missing two months of files. How are
    >you seeing this? I've seen plenty of disk failures, but none of them have
    >managed to lose only new files.
    >
    >> We do daily back ups on a DAT for one week. We
    >> kept getting broadcast messages that backups were successful but when I
    >> tried a backup the tapes had 0 data on them, presumably because it couldn't
    >> read the main drive.

    >
    >Well, that's one painful lesson learned. You have to actually check your
    >backups, and it's important to occaisionally test them to make sure you
    >can restore from them.
    >

    Arcserve has(/had) the ability to check the first n mbytes or all the
    tape.

    I wonder if the OP had the options switched on. Not the first time
    I've heard of zero data on a backup tape. I believe it is quite a
    common occurence.


    --
    AnthonyL

+ Reply to Thread