Can I get LVM to check if my mirrors are consistent?

Question

I'm using LVM mirroring. Following some disk issues I'm concerned about the consistency of the data in my mirrors. Is there anyway I can get LVM to physically compare the data in each mirror?

score 8 · Answer 1 · edited Jan 13 '21 at 13:51

8

It seems from the ticket that added scrubbing that the relevant command is:

lvchange --syncaction check vg/lv

Then wait for lvs -o sync_percent to reach 100% and check that lvs -o mismatches is 0.

I'm unable to test this for myself at present due to not having a recent enough version of LVM.

Thanks to lacasitos and c4f4t0r for the pointers.

Full command to checkout progress/state for Fedora 30:

sudo lvs -o +raid_sync_action,raid_mismatch_count

edited Jan 13 '21 at 13:51

deman_killer

38

answered Dec 23 '13 at 06:35

GS - Apologise to Monica

311

2

Ubuntu 16.04: lvs -o raid_mismatch_count – Tino Oct 10 '17 at 10:52

score 3 · Accepted Answer · answered Dec 22 '13 at 22:31

3

This process is called raid scrubbing, as far as I can see it is supported in Redhat 6.5, not sure about the distro you use.

answered Dec 22 '13 at 22:31

lacasitos

346

any link about lvm raid scrubbing? – c4f4t0r Dec 22 '13 at 23:27
1

https://bugzilla.redhat.com/show_bug.cgi?id=985976 – c4f4t0r Dec 22 '13 at 23:30
Thanks! I proposed an edit to the answer to include the command that needs to be run too. Unfortunately it's not available in my distro, but I'll see if I can upgrade soon. – GS - Apologise to Monica Dec 22 '13 at 23:53
The edit was rejected - perhaps it is a bit too significant a change to someone else's answer - so I've posted another answer with the details. – GS - Apologise to Monica Dec 23 '13 at 06:36

Can I get LVM to check if my mirrors are consistent?

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