Re: is my raid1 array really working??

["Martin Marcher" <martin@marcher.name>]

Hi,

2007/9/18, harland christofferson <debian-user@audubonstrings.com>:
> To me, it looks like HDA and HDC are in good health
> and configured properly ... but what do I really know.
>
> Can someone tell me how I can really know if my
> configuration is working? Is it REALLY this simple?

Disclaimer - read the manpage again before doing that!

# mdadm --detail --scan
# cat /proc/mdstat
# mdadm /dev/md0 --fail /dev/hdc
# mdadm --detail --scan
# cat /proc/mdstat
# mdadm /dev/md0 --remove /dev/hdc
# dd if=/dev/random of=/tmp/testFile bs=1M count=100
# cat /proc/mdstat
# mdadm /dev/md0 --add /dev/hdc
# cat /proc/mdstat

do that to see what happens if a drive fails and is replaced.

of course if you are somewhat confident that your raid work (and boots
from any drive) you can also:

* fail a drive and reboot
* fail a drive and remove it from the RAID, then reboot

/proc/mdstat will always tell you...

hth
martin