On Mon, Jun 06, 2016 at 12:10:23PM -0700, Sarah Newman wrote: > https://www.kernel.org/doc/Documentation/md.txt shows for sync_action > > check - A full check of redundancy was requested and is > happening. This reads all blocks and checks > them. A repair may also happen for some raid > levels. > repair - A full check and repair is happening. This is > similar to 'resync', but was requested by the > user, and the write-intent bitmap is NOT used to > optimise the process. > > I think you wanted 'repair' not 'check'. >From what I understand, the only difference between the 2 is that repair does not use the write-intent bitmap, but both will repair an error if found. https://www.thomas-krenn.com/en/wiki/Mdadm_checkarray#Check_vs._Repair Or are you saying that check after getting a read error from one drive, would not rewrite the bad block on that drive? I thought it did... Either way, it seems that neither would have worked because while those blocks were marked as "need to be reallocated" by the drive, I think the kernel was actually able to read them without problem, so the md layer never saw anything and therefore never did anything either. Whereas badblocks forced an unconditional rewrite of all blocks, and forced the drive to re-allocate those "weak" blocks, even though it was able to read them. Does that sound about right? Marc -- "A mouse is a device used to point at the xterm you want to type in" - A.S.R. Microsoft is to operating systems .... .... what McDonalds is to gourmet cooking Home page: http://marc.merlins.org/ -- 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
