Software RAID + XFS question

[Andrew Mathews]

Federico Voges wrote:
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> Hi,
> 
> Anyone using software RAID (mirroring) on an all XFS system???
> 
> I've installed kernel 2.4.18 + XFS on a COL 3.1.1 and moved all the
> partitions to XFS except for /boot (ext3). The LILO README says
> something about soft RAID devices and XFS but I can't figure how it
> out.

I have 3 machines running XFS and software raid as well as a machine 
running XFS on a hardware raid controller (Perc 3/Di)
My /etc/fstab:
[root at wks1 root]# more /etc/fstab
LABEL=/12               /                       xfs     defaults        1 1
LABEL=/backup12         /backup                 xfs     defaults        1 2
LABEL=/boot12           /boot                   xfs     defaults        1 2
none                    /dev/pts                devpts  gid=5,mode=620  0 0
LABEL=/home12           /home                   xfs     defaults        1 2
LABEL=/iso12            /iso                    xfs     defaults        1 2
LABEL=/opt12            /opt                    xfs     defaults        1 2
none                    /proc                   proc    defaults        0 0
none                    /dev/shm                tmpfs   defaults        0 0
LABEL=/tmp12            /tmp                    xfs     defaults        1 2
LABEL=/usr12            /usr                    xfs     defaults        1 2
LABEL=/var12            /var                    xfs     defaults        1 2
/dev/sda6               swap                    swap    defaults        0 0
/dev/cdrom              /mnt/cdrom              iso9660 
noauto,owner,kudzu,ro 0 0
/dev/fd0                /mnt/floppy             auto 
noauto,owner,kudzu 0 0

> It's not a problem to have /boot use ext3 but I'd like to use only XFS.
> 
> Another question: if I use install=/dev/md0 (/boot) in /etc/lilo.conf
> and the primary disk fails (and I remove it), the system should boot
> from the second disk, right??

Yes.

> Finally, I've partitioned the disk like this:
> md0 50MB   /boot   (ext3)
> md1 7GB    /       (xfs)
> md2 512MB          (swap)
> md3 22GB   /home   (xfs)
> 
> Any sugestions about this partitioning scheme?? Acording to hdparm
> tests, /dev/md2 is faster than the others (I guess that's because it's
> located near the middle of the disk):

Looks okay, but it also depends on your own choice. I personally prefer 
to have as much as possible on individual partitions.

<snip>
What does your /etc/raidtab look like? Should look something like:
raiddev             /dev/md0
raid-level                  0
nr-raid-disks               2
chunk-size                  64k
persistent-superblock       1
nr-spare-disks              0
     device          /dev/sdb1
     raid-disk     0
     device          /dev/sdc1
     raid-disk     1
-- 
Andrew Mathews
-------------------------------------------------------
andy.nmcourts.com  Monday Jun 17 2002 15:35:00 MDT
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A Los Angeles judge ruled that "a citizen may snore with immunity in
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