When you tried to attach the cache, did the file you were echoing to exist? That looks correct but I'm not sure what else would generate that error. For the UUIDs to show up in blkid, blkid itself would have to be updated to know about the bcache superblock (IIRC it lives in util-linux). I should probably ping the author and see if that can get included. If you have the udev rules and probe-bcache installed, the symlinks /ought/ to show up when you reboot but I haven't tested that in ages. I just got the code written so that it ought to be able to work on top of md devices again, which means I should be able to run it at home and I'll have to fix probe-bcache if it's broken then :) On Mon, Nov 14, 2011 at 3:10 PM, Justin Rush <jarush@xxxxxxxx> wrote: > Using 3.1.0-rc9 > > I created a cache device on /dev/sdk1 > # ./make-bcache -C -b512k -w4k --writeback /dev/sdk1 > > and a backing device on /dev/md127p1. > ./make-bcache -B /dev/md127p1 > > # ./probe-bcache /dev/sdk1 > 5f42bdd1-4342-4ab6-8dda-855989a09604: UUID="" TYPE="bcache" > > # ./probe-bcache /dev/md127p1 > 6bbac9a4-afbd-4d40-9562-cdd290622c5d: UUID="" TYPE="bcache" > > I then registered them by: > # echo /dev/sdk1 >/sys/fs/bcache/register # echo /dev/md127p1 >/sys/fs/bcache/register > > I have /dev/bcache0 > > When I try to attach the cache, I get this: > # echo "5f42bdd1-4342-4ab6-8dda-855989a09604" >/sys/block/md127/md127p1/bcache/attach > -bash: echo: write error: No such file or directory > > I believe this problem is due to the UUIDs for the two devices, but this is just a guess. The UUID for /dev/sdk1 and /dev/md127p1 doesn't appear to be registering properly as they don't show up in blkid. I tried specifying the UUID to use with the -U option when creating the devices, but that didn't seem to help. I do have the udev rules file from the tools in place > > Does anyone know what is going on here and how to fix it? > > Justin Rush > jarush@xxxxxxxx > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-bcache" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
