I’ve been experimenting a bit with dmraid eventing,
and I notice that when I do the following, the result is not what I expect –
but perhaps someone can enlighten me on what is truly expected:
- Setup a RAID0+1 with dmraid
- Register the RAID using
dm_dso_reg_tool. I also ensure that it is properly registerd using “dm_dso_reg_tool
- I note the major and minor
number of the devices that comprise the RAID, using “dmsetup status”.
- I start a write onto the RAID
volume using a large file (3GB).
- During the write process, I
pull one of the RAID member disks out so that I may simulate a RAID
- I notice that the “dmsetup
status” command shows one of the disks as being marked disabled –
which is good. I take note of the disabled disk’s major:minor
- I reconnect the RAID member
disk that I pulled out in step 5. When I look for that disk’s
major:minor numbers using “ls –l /dev/sd*”, I don’t
see that major:minor number pair.
- When I run “dmsetup
status” again, the major:minor numbers for the pulled disk is still
the same as the one I saw in Step 3.
What I expected was that the major:minor number pair for the
pulled disk would correspond to the one that I saw in Step 7. Is my assumption
incorrect? The reason why I was expecting it this way was because I was
thinking that if I use dmsetup to determine the RAID status and see a disabled
drive, I can follow it back to a /dev/sd* and then get the hard drive’s
serial number – then I would know which member disk to replace. Is there
a better way?
Thanks for clarifying,