component device mismatches found

component device mismatches found

[Gandalf Corvotempesta]

I've seen this in my log:

Mar 19 00:57:01 x /USR/SBIN/CRON[17832]: (root) CMD (if [ -x
/usr/share/mdadm/checkarray ]; then /usr/share/mdadm/checkarray --cron
--all --idle --quiet; fi)
Mar 19 00:57:01 x mdadm[1576]: RebuildStarted event detected on md
device /dev/md/0
Mar 19 01:30:21 x mdadm[1576]: Rebuild24 event detected on md device /dev/md/0
Mar 19 02:03:41 x mdadm[1576]: Rebuild47 event detected on md device /dev/md/0
Mar 19 02:37:02 x mdadm[1576]: Rebuild68 event detected on md device /dev/md/0
Mar 19 03:10:22 x mdadm[1576]: Rebuild87 event detected on md device /dev/md/0
Mar 19 03:38:00 x mdadm[1576]: RebuildFinished event detected on md
device /dev/md/0, component device  mismatches found: 4608

This is a 3way mirror.

I've tought that swap was the culpit, but swap isn't used:

# free -m
             total       used       free     shared    buffers     cached
Mem:         32230      31844        386          0       1679      26026
-/+ buffers/cache:       4137      28092
Swap:         8191          0       8191

and IIRC, linux never clean the swap usage up to 0.

Are my data safe ? Is something to be worried about ?

Re: component device mismatches found

[Wols Lists]

On 19/03/17 10:00, Gandalf Corvotempesta wrote:
> I've seen this in my log:
> 
> Mar 19 00:57:01 x /USR/SBIN/CRON[17832]: (root) CMD (if [ -x
> /usr/share/mdadm/checkarray ]; then /usr/share/mdadm/checkarray --cron
> --all --idle --quiet; fi)
> Mar 19 00:57:01 x mdadm[1576]: RebuildStarted event detected on md
> device /dev/md/0
> Mar 19 01:30:21 x mdadm[1576]: Rebuild24 event detected on md device /dev/md/0
> Mar 19 02:03:41 x mdadm[1576]: Rebuild47 event detected on md device /dev/md/0
> Mar 19 02:37:02 x mdadm[1576]: Rebuild68 event detected on md device /dev/md/0
> Mar 19 03:10:22 x mdadm[1576]: Rebuild87 event detected on md device /dev/md/0
> Mar 19 03:38:00 x mdadm[1576]: RebuildFinished event detected on md
> device /dev/md/0, component device  mismatches found: 4608
> 
> This is a 3way mirror.
> 
> I've tought that swap was the culpit, but swap isn't used:
> 
> # free -m
>              total       used       free     shared    buffers     cached
> Mem:         32230      31844        386          0       1679      26026
> -/+ buffers/cache:       4137      28092
> Swap:         8191          0       8191
> 
> and IIRC, linux never clean the swap usage up to 0.
> 
> Are my data safe ? Is something to be worried about ?

mdadm --detail /dev/md/0

I think we need a bit more info - it's not ringing any alarm bells for
me, but I'm not an expert.

Cheers,
Wol

Fwd: component device mismatches found

[Gandalf Corvotempesta]

/cc linux-raid


---------- Forwarded message ----------
From: Gandalf Corvotempesta <gandalf.corvotempesta@gmail.com>
Date: 2017-03-19 11:42 GMT+01:00
Subject: Re: component device mismatches found
To: Wols Lists <antlists@youngman.org.uk>


2017-03-19 11:21 GMT+01:00 Wols Lists <antlists@youngman.org.uk>:
> mdadm --detail /dev/md/0

# mdadm --detail /dev/md0
/dev/md0:
        Version : 1.2
  Creation Time : Mon Jul 25 12:55:48 2016
     Raid Level : raid1
     Array Size : 488382841 (465.76 GiB 500.10 GB)
  Used Dev Size : 488382841 (465.76 GiB 500.10 GB)
   Raid Devices : 3
  Total Devices : 3
    Persistence : Superblock is persistent

    Update Time : Sun Mar 19 11:38:53 2017
          State : clean, recovering
 Active Devices : 3
Working Devices : 3
 Failed Devices : 0
  Spare Devices : 0

 Rebuild Status : 83% complete

           Name : x:0  (local to host x)
           UUID : b2a5ed53:42890b73:dc6de22a:1ac12524
         Events : 29170

    Number   Major   Minor   RaidDevice State
       0       8        1        0      active sync   /dev/sda1
       1       8       17        1      active sync   /dev/sdb1
       2       8       33        2      active sync   /dev/sdc1




keep in mind that:
1) i've done a check this morning, after seeing the mismatch error in syslog
2) even this check has triggered a rebuild, probably due to the same mismatch.
3) SMART doesn't report any errors,
4) disks are "new", 5600 hours.
5) swap is still unused