Retired_Member wrote:

StephenB

Then be so kind to share the advantage(s) of doing scrub with bitrot protection off, please.

You are going off topic, but I will answer anyway.

The scrub maintenance task includes both a btrfs scrub and a raid scrub. Note that the raid scrub is available on older OS 4.2.x readynas as it's own maintenance function (even though OS4.2 has no bitrot protection).

The btrfs scrub provides some verification of the file system integrity, even if there are no checksums. The raid scrub also verifies that all the parity blocks in the RAID system are consistent with the data blocks. If a bad disk block is encountered during either scrub, the block should be re-allocated and it's contents reconstucted from the remaining data+parity blocks. And of course, the SMART logs will track the reallocated and pending sectors that are uncovered.

There are some posts about scrubs not being useful with jbod volumes (and checksums turned off). But that's a different setup than what we have here. Even then, I suspect that scrubs in those cases might still have some diagnostic value.

mdgm wrote:

Which services are you running?

Which apps do you have installed?

Dahwich - it would be good to follow up with mdgm-ntgr on this, as something does appear to be interfering with the normal scrub.

Forum Discussion

CG3000v2 network priority control