On 11/10/2013 2:34 PM, NeilBrown wrote: > On Sun, 10 Nov 2013 13:17:21 -0600 Stan Hoeppner <stan@xxxxxxxxxxxxxxxxx> > wrote: > >> Also, I see little/no value in running a scheduled mdadm check on a >> RAID1 array. Any problems with RAID1 will be due to one of the disks >> beginning to fail in some mode, usually requiring sector relocation. > > I think scrubbing has value on any RAID with redundancy. That's a bit... redundant, Neil. :) > The firmware can only relocate a sector if it reads it when it is marginal > but not yet completely lost. If a sector is not read for a long time and > during that time the media degraded beyond recovery the firmware cannot do > anything. But RAID1 can - it can get it from the other device. But is a scrub required for this? Isn't this exactly what occurs during normal operation with md/RAID1? I.e. a read fails with disk error, so we grab the sector from the mirror? So what advantage is there to scrubbing md/RAID1? -- Stan -- 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
