=====Vérifier l'état d'un RAID=====
<code bash>
cat /proc/mdstat
</code>

Et ''[UU]'' doit apparaître.

[[https://wiki.gentoo.org/wiki/Complete_Handbook/Software_RAID|Complete Handbook_Software RAID - Gentoo Wiki]] {{ :linux:raid:complete_handbook_software_raid_-_gentoo_wiki_2019-12-13_3_31_11_pm_.html |Archive du 09/01/2019 le 13/12/2019}}

Motif d'une demande de resync :
<code>
[    4.354617] md/raid1:md0: not clean -- starting background reconstruction
[    4.354689] md/raid1:md0: active with 2 out of 2 mirrors
[    4.354829] md0: bitmap file is out of date (26019 < 26020) -- forcing full recovery
[    4.354922] md0: bitmap file is out of date, doing full recovery
[    4.460356] md0: detected capacity change from 0 to 2988307382272
[    4.460529] md: resync of RAID array md0
</code>

En cas de resynchronisation :
<code>
Personalities : [raid1] 
md0 : active raid1 sdd1[1] sdb1[0]
      2918268928 blocks super 1.2 [2/2] [UU]
      [==>..................]  resync = 10.1% (296512384/2918268928) finish=425.7min speed=102632K/sec
      bitmap: 20/22 pages [80KB], 65536KB chunk
</code>

La vitesse se personnalise avec ''/proc/sys/dev/raid/speed_limit_min'' et ''/proc/sys/dev/raid/speed_limit_max'', en Ko.