Re: Can linux support hotswap ?

From: Fatih Gey (fatih.gey_at_epost.de)
Date: 06/05/04

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    Date: Sat, 5 Jun 2004 19:29:49 +0200
    
    

    Hi Darick,

    i think you mixed something up ..

    If you want to increase your data's integrity against harddisk failures,
    you need to set up a "raid array". For common integrity use, you should take
    RAID-1 (mirror) or RAID-5 (spread parity)
    Please refere to a complete Documentation, if you need more detail on that..

    Linux (e.g. Red Hat v9.0) supports a Software-Emulation of RAID-Technology..
    ..afaik, it does by offering kernelspace driver to define an disc array and
    let them (/dev/md*)
    behave like a regular disc .. so you can e.g. create partitions and format
    the
    whole array as doing it for example with /dev/hda

    Exchanging a Disc while your Linux Box is running should not be a problem
    for your Linux
    (at least for Software-side) .. as far as you 're not running your System on
    this disc array *g*:
    Unmounting and unloading the controller driver before taking the disc out of
    your system should work..
    but I'm confident that your Hardware e.g. your disc controller WILL NOT like
    it.

    If your System really needs to be kept up despite an harddisc failure, I'd
    advise you to
    take an Disc Controller that already supports RAID (take care of
    "hotswap/hotspare"
    capability). A good choice are 3ware raid-controller .. they all provide
    good-working
    and feature-filled Linux Software..

    This time, your HW-Controller does the "disc array -> disc" emulation.. So
    for your Linux,
    the array seems to be a regular harddisc.. using the provided Linux-Software
    you can control
    your HW Raid-Controller's Emulation.

    Now your Controller is made to take a disc off while running your system, so
    it could manage it
    silencely: After having your corrupt disc exchanged your controller will
    initialize the new disc - e.g.
    if you're using mirror (RAID-1), it will copy existing data to the new disc
    automaticly..

    Hope, i' could fill your question ..
    Regards

    Fatih Gey

    P.S.: http://www.tldp.org/HOWTO/Software-RAID-HOWTO.html gives you a good
    overview about
    RAID

    "Darick" <darick_ang@yahoo.com.sg> schrieb im Newsbeitrag
    news:72gqb0t7cc487rnmhd5rco83ra3u3i6psj@4ax.com...
    > first, i like to know, can linux support hotswap ? i using RH9, may i
    > know how to configure ?
    >
    > second, i like to know how hotswap mirroring the data ? i hope is not
    > on file basis


  • Next message: Fatih Gey: "Re: Invalid unicode in Fedora Core 2"

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