Windows 2000
Booting From Mirror After Primary Partition Is Lost
Changing Active Partition Can Make Your System Unbootable
Linux
http://www.tldp.org/HOWTO/Software-RAID-HOWTO.html
The raid config is stored in /etc/raidtab
Slow Resync
On RH8, the resynch is much slower than Win2000 because it will resynch the whole hard disk, not just the modified blocks. There is a faster raid driver, but i'm not confident enough to install it.
On crash, mirrors will resynch, with the original being raid disk 0, and the mirror being raid disk 1. This is very slow. To stop resync, read /etc/raidtab and then run:
raidsetfaulty <raid-device> <mirror-hard-disk-device>eg. for mobydick (see raidtab below):
raidsetfaulty /dev/md0 /dev/hdb1
Later, in the evening, restart the raid resynch by:
raidhotremove /dev/md0 /dev/hdb1 raidhotadd /dev/md0 /dev/hdb1
Moby Dick raidtab
>> cat /etc/raidtab
raiddev /dev/md0
raid-level 1
nr-raid-disks 2
chunk-size 64k
persistent-superblock 1
nr-spare-disks 0
device /dev/hda2
raid-disk 0
device /dev/hdb1
raid-disk 1
Linux Rescue
a. On crash and you cannot restart, then try reboot using Red Hat rescue CD. You will be prompted to enter a rescue command at the LILO prompt. Then it will go through part of the install process (to configure keyboard and language), so don't be too concerned that you are reinstalling). The rescue mode will then mount the original root file system at /mnt/sysimage. Now you can continue with repairs...
b. after mounting , view (cat) /mnt/sysimage/etc/fstab and /mnt/sysimage/etc/raidtab
c. run fsck -t [type from fstab] [/dev/? from fstab]
d. reboot from hard disk
e. After reboot, mirrors will resync. Use cat /proc/mdstat to monitor sync progress.