moving software raid set from one system to another

[Martin Stone]

A few thoughts:

1. use fdisk -l and just make sure that the partitions you think make up your md 
device are the ones you're trying to add (i.e., make sure /dev/hde1 is the size 
you expect, is partition type "fd", etc).

2. make sure that what's in /etc/raidtab matches what you learned from fdisk.

3. use a persistent superblock next time :-P

4. if you're stuck, how about posting the contents of /etc/raidtab and the 
output of fdisk -l ... that'd be a big help in figuring out what's going on...

Good luck!

Dan Bongert wrote:
> So, I had a system partition fail the other day, and ended up needing to
> completely reinstall my home server. I had a data drive was a software raid
> set consisting of two 120GB hard drives striped together. After making sure
> everything was up and running, I tried remounting the data partition. I added
> its configuration to/etc/raidtab, and ran 
> 	raidstart /dev/md6
> (raid devices 0 through 5 are the new system mirrors on my server). However
> this got me an error message:
> 	/dev/md6: Invalid argument
> 
> Any thoughts? mkraid will wipe the disks, which is exactly what I don't want.
> I ran across a tool called mdadm, but when I use that in examine mode, I get
> this:
> 
> navi(52) ~/mdadm-1.5.0> sudo mdadm -E /dev/hde1
> mdadm: No super block found on /dev/hde1 (Expected magic a92b4efc, got
> c59ec5e0) navi(53) ~/mdadm-1.5.0> sudo mdadm -E /dev/hdf1
> mdadm: No super block found on /dev/hdf1 (Expected magic a92b4efc, got
> 632b70d8
> 
> I *know* the drives were working properly, though for the life of me I can't
> remember why I didn't create them with a persistent superblock. (I think this
> is why mdadm is failing).
>