Talk about missing the email I wanted to reply too. Disregard... >> On Mar 10, 2017, at 9:28 AM, Valeri Galtsev <galtsev at kicp.uchicago.edu> wrote: >>> >>> >>> On Fri, March 10, 2017 9:52 am, Warren Young wrote: >>>> On Mar 10, 2017, at 6:32 AM, James B. Byrne <byrnejb at harte-lyne.ca> wrote: >>>>> >>>>> On Thu, March 9, 2017 09:46, John Hodrien wrote: >>>>>> >>>>>> fsck's not good at finding disk errors, it finds filesystem errors. >>>>> >>>>> If not fsck then what? >>>> >>>> badblocks(8). >>> >>> And I definitely will unmount relevant filesystem(s) before using >>> badblocks… >> >> You don’t necessarily have to. The default mode of badblocks is a non-invasive read-only test >> which is safe to run on a mounted filesystem. >> >> That said, a read-only badblocks pass can give a false “no errors†report in cases where a >> non-destructive read-then-write pass (-n) will show errors. >> >> Alternatively, a read-only pass may show an error that a read-then-write pass will silently bury >> by forcing the drive to relocate the bad sector. >> >> In extreme cases, you could potentially fix a problem with a read-random-random-write pass (-n >> -t >> random -t random) because that will statistically flip all the bits at least twice, which may >> rub >> the drive’s nose in a bad sector, forcing a reallocation where a normal read-then-write pass >> (-n >> alone) may not. >> >> Hard drives are weird. It is only through the grace of ECC and such that they approximate >> deterministic behavior as well as they do. >> _______________________________________________ >> CentOS mailing list >> CentOS at centos.org >> https://lists.centos.org/mailman/listinfo/centos >> > > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > https://lists.centos.org/mailman/listinfo/centos >