Re: Managing a 0.5Tb RAID

From: John-Paul Stewart (jpstewart_at_sympatico.ca)
Date: 08/13/03

  • Next message: Måns Rullgård: "Re: C-Media CMI8738 card?" 
    Date: Wed, 13 Aug 2003 11:29:07 -0400

    [Note follow-ups set to c.o.l.hardware. This appears to be a general
    Linux discussion, not RedHat specific, and not SCSI-specific.]

    "Roman M. Parparov" wrote:
    >
    > In comp.periphs.scsi John-Paul Stewart <jpstewart@sympatico.ca> wrote:
    > > "Roman M. Parparov" wrote:
    > >
    > > Try a different filesystem. At a minimum, use ext3. (You don't want to
    > > wait all day for fsck to run on a 500GB ext2 partition.) JFS or XFS
    > > might be even better choices.
    >
    > AFAIK ext3 is limited to 64GB...

    I've never seen that documented anywhere. Ext2 can handle at least 2TB
    (see Documentation/filesystems/ext2.txt in the kernel source tree).
    Ext3 appears to have the same limitations as ext2.
     
    > >
    > > FWIW, I'm using a slightly smaller (5x73GB) software RAID 5 in one of my
    > > systems with JFS. No problems whatsoever with it (yet) in the three
    > > months since it was installed.
    >
    > You just ran an mkfs over the partition fdisk reported, or you used LVM
    > first?

    I'm using software RAID, so I had to do a mkraid between fdisk (on the
    physical disks) and mkfs (on the logical RAID volume). I'm not using
    LVM at all. It's not entirely clear to me what you're trying accomplish
    with LVM. I presume your RAID hardware presents itself as a single
    large volume, right? In that case, I think fdisk and mkfs are all you
    need. (LVM shouldn't cause any problems, but shouldn't be strictly
    necessary, either.)

    > >
    > > Other than that, what RAID controller are you using? Is it an external
    > > box that does the RAID and holds the disks, connecting to a normal SCSI
    > > channel (e.g., Sun A1000)? Or is it a PCI RAID card connected to an
    > > external disk enclosure?
    >
    > It's an external box (RaidTec FlexArray HI 12)

    OK. So the external box is doing the RAID. It could be a configuration
    problem with the box. It's harder to diagnose this way.

  • Next message: Måns Rullgård: "Re: C-Media CMI8738 card?"

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