On 12/06/2017 05:49 AM, Andreas Klauer wrote: > On Wed, Dec 06, 2017 at 03:33:36PM +1100, Jeremy Graham wrote: >> How do I "manually regenerate content for each block in BBL's and then >> manually zero the lists in superblocks"? This is uncharted (and >> slightly scary) territory for me. > > You don't. Just mdadm --assemble it with --update=force-no-bbl here. The problem with this is that the sectors currently marked don't have appropriate data. So garbage will be read in those locations after the BBL is deleted. There's only two approaches with any hope of rescuing the content: 1) Backup everything that is known to involve the BBL sectors, then restore those files after the BBL is deleted. 2) Use hdparm to fake bad sectors on the underlying device in the same locations as the BBL. Then run a scrub after the BBL is deleted. A bit risky, as MD only allows 10 UREs per hour before kicking a drive. The array might need --assemble --force multiple times to complete the scrub. > 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. The BBL in MD is woefully incomplete and should *never* be used. Phil -- 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
