On Sat, Apr 06, 2013 at 10:43:13AM +0000, Stuart Henderson wrote: > On 2013-04-04, Juha Erkkila <j...@turnipsi.no-ip.org> wrote: > > Hello misc, > > > > I am having a problem with a mirroring softraid configuration. > > Every time I try to access a particular partition in softraid > > volume I start to get I/O errors so that softraid totally "breaks", > > that is, becomes non-operative. > > > > Note that it does very much look like that both of these > > disks are actually defective. > > > Note that I said that I think both disks are defective. When > > the system is booted with softraid disabled and then the disks > > (sd0 and sd1) are read with > > "dd if=/dev/rsd0c of=/dev/null conv=noerror,sync", > > dd reports several I/O errors (a few such errors every now and then). > > You might want to try different cables, though really it sounds > like it's probably time to restore from your backups.
Well I do have backups, but I did not want to go that route because my most recent backup did not have my latest files, and I wanted to recover those. Anyway, I did find out a way to recover the data. Basically I just read the other disk in the softraid mirror, stripping the softraid metadata, like this: $ dd if=/dev/sd0d of=shifted-raid.img conv=noerror,sync skip=528 Some read errors occured, though, but oh well. And then: $ vnconfig vnd0 shifted-raid.img $ fsck /dev/vnd0h $ dump -0a -f vnd0h.dump /dev/vnd0h Worked like a charm ;-) I guess there might have been an easier way, but I could not figure it out. Before giving I/O errors softraid reported ``softraid0: retrying read on block 591205648''. Perhaps this will help someone else who runs into this somewhere, later. Juha
