On Thursday July 6, john@xxxxxxxxxxx wrote: > > Neil, > > First off, thanks for all your hard work on this software, it's really > a great thing to have. > > But I've got some interesting issues here. Though not urgent. As > I've said in other messages, I've got a pair of 120gb HDs mirrored. > I'm using MD across partitions, /dev/hde1 and /dev/hdg1. Works > nicely. > > But I see that I have an old superblock sitting around on /dev/hde > (notice, no partition here!) which I'd like to clean up. > ... > > I can't seem to zero it out: > > # mdadm --misc --zero-superblock /dev/hde > mdadm: Couldn't open /dev/hde for write - not zeroing > > Should I just ignore this, or should I break off /dev/hde from the > array and scrub the disk and then re-add it back in? You could ignore it - it shouldn't hurt. But if you wanted to (and were running a fairly recent kernel) you could mdadm --grow --bitmap=internal /dev/md0 mdadm /dev/md0 --fail /dev/hde1 --remove /dev/hde1 mdadm --zero-superblock /dev/hde mdadm /dev/md0 --add /dev/hde1 mdadm --grow --bitmap=none /dev/md0 and it should work with minimal resync... Though thinking about it - after the first --grow, check that the unwanted bitmap is still there. It is quite possible that the internal bitmap will over-write the unwanted superblock (depending on the exact size and aligment of hde1 compared with hde). If it is gone, then don't bother with the rest of the sequence. > > Also, can I upgrade my superblock to the latest version with out any > problems? The only problem with superblock version numbers is that they are probably confusing. If you don't worry about them, they should just do the right thing. NeilBrown - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
