[CentOS] How to enable my RAID again

Fri Oct 5 09:04:59 UTC 2007
Theo Band <theo.band at xanadu-wireless.com>

Hi

I have setup software RAID two years ago using FC3 using the graphical
installer (RAID1). In the mean time I installed CENTOS4.5 and everything
is running fine. At least that was my perception. It now turns out that
raid is not working and that LVS just finds 4 partitions from four disks
and that's it.:

  /dev/sda2  VolGroup00 lvm2 a-   94.88G     0
  /dev/sdb1  VolGroup00 lvm2 a-   94.94G 10.00G
  /dev/sdc1  VolGroup00 lvm2 a-   94.94G 74.94G
  /dev/sdd1  VolGroup00 lvm2 a-   94.94G 70.81G

These are 4 disk of each 200GB, and the disks have these partitions:

Using /dev/sda
(parted) print
Disk geometry for /dev/sda: 0.000-194481.000 megabytes
Disk label type: msdos
Minor    Start       End     Type      Filesystem  Flags
1          0.031    101.975  primary   ext3        boot
2        101.975  97284.243  primary               lvm
3      97284.243 194474.355  primary               raid
Disk geometry for /dev/sdb: 0.000-194481.000 megabytes
Disk label type: msdos
Minor    Start       End     Type      Filesystem  Flags
1          0.031  97237.177  primary               boot, lvm
2      97237.178 194474.355  primary               raid
Disk geometry for /dev/sdc: 0.000-194481.000 megabytes
Disk label type: msdos
Minor    Start       End     Type      Filesystem  Flags
1          0.031  97237.177  primary               boot, lvm
2      97237.178 194474.355  primary               raid
Disk geometry for /dev/sdd: 0.000-194481.000 megabytes
Disk label type: msdos
Minor    Start       End     Type      Filesystem  Flags
1          0.031  97237.177  primary               boot, lvm
2      97237.178 194474.355  primary               raid

So my feeling is that I need to setup the RAID again, but I don't want
to make any mistakes here, since this is a live system working fine. I
tried to read the mdadm manual but it's not quit clear to me what to do.
# mdadm -A --scan -v
mdadm: No arrays found in config file

Shows I have to do more. The previous fedora installation is still
around, but is doesn't contain a /etc/mdadm.conf file.

Can anyone help me with some steps to take to get it running again. I do
have backups, but if things go wrong restoring takes several hours.

Thanks,
Theo


PS.
Send for the third time. Could it be that posting is limited to email
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