On Thu, Sep 29, 2011 at 09:25:05PM +0100, Robin Hill wrote: > On Thu Sep 29, 2011 at 03:37:05PM -0400, William Thompson wrote: > > > On Thu, Sep 29, 2011 at 08:26:11PM +0100, Robin Hill wrote: > > > You don't need to recreate the raid at all, just reassemble it. You may > > > want to update the homehost though, otherwise it will (IIRC) auto > > > assemble to md_126 (or so) instead of md0. > > > > The reason I asked this was because a mirrored pair that I currently have is > > 0.90 version and I was going to use 1.0 > > > You _should_ be able to do a --create --assume-clean there, without > losing the data, but I'd go with a backup, --create, and restore jsut to > be safe. Agreed, however, in this case, I was going for a new raid with new data and the disks would already be in sync. > > > ability to check the array for mismatches though, and the recovery > > > process would bring everything into sync whenever it's run anyway. More > > > > I've rarely done this. On large disks, this takes may hours to perform. > > > It can, but it also ensures the disks are readable. If you don't run > regular checks, in a recovery situation you may hit a bad block on a > supposedly good disk and have a heap more trouble to deal with. Understood. > > > of a question would be why not do the initial recovery? It doesn't delay > > > access to the array, and at least the I/O load is happening at a > > > controlled point (rather than at recovery time, when you have no > > > > I guess the only reason I can come up with would be to avoid extra head > > seeks. Well, that and the time it takes. > > > > During the initial sync, if a write happens to an area that has been synced, > > does it go to all drives? What about a write to an area that as not been > > synced yet? > > > If the area has already been synced then writes will definitely go to > all members. I'm pretty sure this also happens in areas which haven't > been synced as well, but I'm not 100% on that. Ok, thanks. -- 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
