On Wed, Dec 06, 2017 at 09:15:21AM -0500, Phil Turmel wrote: > The problem with this is that the sectors currently marked don't have > appropriate data. It might have the correct data. Depends what exactly happened. If it happened years ago and you never noticed until reshape, chances are it won't matter one way or another. Of course, it doesn't hurt to take additional steps, if you have backups to compare with or some other way to check file integrity. > > If you have a filesystem with bad blocks management on top of it, > > check that too and clear it if necessary. > > MD's BBL system doesn't coordinate with the filesystem on top, so this > is meaningless. MD with duped BBLs does return read errors, so it's a possibility. > The BBL in MD is woefully incomplete and should *never* be used. There's ups and downs to everything. Relocations would be awful too. Harms performance and makes recovery all but impossible. So many people on this list with lost metadata, figuring out RAID layout and drive oder is hard, but figuring out random relocations is impossible. The BBL could be improved a lot if it prevented BBLs to be identical across drives, and gave bad blocks a second chance. Once the cable problem is solved, MD should help you turning those bad blocks back into good ones. And if your drive actually has real bad blocks, the only correct course of action is to replace it entirely. The problem with BBL right now is that even if you replace all drives, the BBL stays. Once it's duplicated you are stuck with it forever until you forcibly remove it. Regards Andreas Klauer -- 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
