[RndTbl] Big-endian RAID5 recovery problem
athompso at athompso.net
Mon May 1 17:33:11 CDT 2017
On 2017-05-01 16:59, Anthony Youngman wrote:
> Get hold of lsdrv, and see what that tells you. (Look at the raid wiki
> for details.) I don't know if it will have endian issues, but if it
> doesn't an expert will probably be able to chime straight in and tell
> you the create command.
Ah! And that took me straight to the "asking for help" page.
The raw data is here:
* smartctl either fails to run or shows nothing wrong (depending on the
vintage of drive, maybe?);
* mdadm --examine fails to read the superblock because of the endianness
* lsdrv fails to report any useful MD topology information I could see
(other than confirming that each md device had four members, one
partition on each drive)
I also see 3 "FD" type partitions on each disk, but lsdrv only
identifies *2* of them as belonging to an MD array. Not sure what's up
> The other thing is, read up on overlays because, if you overlay those
> disks, you will be able to "create" without actually writing to the
> disks. That way you can test - and even do a complete backup and
> recovery - without ever actually writing to, and altering, the
> original disks.
Currently reading, thanks. Didn't know overlays could be used for block
Spinning up a QEMU instance of Linux-PPC or Linux-MIPS with the disks in
pass-through mode has also been mentioned, but... ugh. Anecdotal
reports from the web suggest that doing so would just be opening up a
second rabbit hole in addition to the one I'm already headed down.
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