mdadmを使用してubuntu 14.04でIntel RSTソフトウェアRAIDを実行しました。 （Raid 5の4 x 6TBドライブ、デバイス名/ devで作成）
sudo mdadm -C /dev/md/imsm /dev/sda /dev/sdb /dev/sdh /dev/sdi -n 4 -e imsm
sudo mdadm -C /dev/md/vol0 /dev/md/imsm -n 4 -l 5
これで出力されます（数回再起動した後の様子）。
sudo mdadm --query --detail /dev/md/vol0
/dev/md/vol0:
Container : /dev/md/imsm0, member 0
Raid Level : raid5
Array Size : 17581557760 (16767.08 GiB 18003.52 GB)
Used Dev Size : -1
Raid Devices : 4
Total Devices : 4
State : clean, resyncing
Active Devices : 4
Working Devices : 4
Failed Devices : 0
Spare Devices : 0
Layout : left-asymmetric
Chunk Size : 128K
Resync Status : 54% complete
UUID : 9adaf3f8:d899c72b:fdf41fd1:07ee0399
Number Major Minor RaidDevice State
3 8 112 0 active sync /dev/sdh
2 8 16 1 active sync /dev/sdb
1 8 0 2 active sync /dev/sda
0 8 144 3 active sync /dev/sdj
常に再同期の問題は、システムが起動後に一貫していないようにデバイス名を変更することです（例：/dev/sda ->突然/dev/sdiになるなど）。
sudo mdadm --detail --scan
ARRAY /dev/md/imsm0 metadata=imsm UUID=e409a30d:353a9b11:1f9a221a:7ed7cd21
ARRAY /dev/md/vol0 container=/dev/md/imsm0 member=0 UUID=9adaf3f8:d899c72b:fdf41fd1:07ee0399
mdadmツール出力：
sudo mdadm --examine /dev/md/imsm0
/dev/md/imsm0:
Magic : Intel Raid ISM Cfg Sig.
Version : 1.3.00
Orig Family : 68028309
Family : 68028309
Generation : 00002f29
Attributes : All supported
UUID : e409a30d:353a9b11:1f9a221a:7ed7cd21
Checksum : 85b1b0cb correct
MPB Sectors : 2
Disks : 4
RAID Devices : 1
Disk00 Serial : WD-WXL1H84E5WHF
State : active
Id : 00000002
Usable Size : 11721038862 (5589.03 GiB 6001.17 GB)
[vol0]:
UUID : 9adaf3f8:d899c72b:fdf41fd1:07ee0399
RAID Level : 5 <-- 5
Members : 4 <-- 4
Slots : [UUUU] <-- [UUUU]
Failed disk : none
This Slot : 0
Array Size : 35163115520 (16767.08 GiB 18003.52 GB)
Per Dev Size : 11721038848 (5589.03 GiB 6001.17 GB)
Sector Offset : 0
Num Stripes : 45785308
Chunk Size : 128 KiB <-- 128 KiB
Reserved : 0
Migrate State : repair
Map State : normal <-- normal
Checkpoint : 5191081 (1024)
Dirty State : clean
Disk01 Serial : WD-WX51DA476UL6
State : active
Id : 00000001
Usable Size : 11721038862 (5589.03 GiB 6001.17 GB)
Disk02 Serial : WD-WX51DA476P65
State : active
Id : 00000000
Usable Size : 11721038862 (5589.03 GiB 6001.17 GB)
Disk03 Serial : WD-WX51DA476HS5
State : active
Id : 00000003
Usable Size : 11721038862 (5589.03 GiB 6001.17 GB)
では、汚れた状態はきれいだという意味ですか？それでは、なぜ再同期する必要がありますか？潜在的な問題がどこにあるかを知っている人はいますか？
私のdmesg tail出力には以下が表示されます。 SAS ata7ポートがないとします（おそらくBIOSでMarvell SASコントローラがオフになっているようです）。 SATポートは6個、SASポートは2個（オフ）のみです。
[ 4064.913017] sr 0:0:0:0: command ffff8802fc4ccc00 timed out
[ 4064.913043] sas: Enter sas_scsi_recover_host busy: 1 failed: 1
[ 4064.913048] sas: ata7: end_device-0:0: cmd error handler
[ 4064.913092] sas: ata7: end_device-0:0: dev error handler
[ 4064.913529] sas: --- Exit sas_scsi_recover_host: busy: 0 failed: 0 tries: 1
[ 4064.913874] sr 0:0:0:0: command ffff8802fb703b00 timed out
[ 4064.913896] sas: Enter sas_scsi_recover_host busy: 1 failed: 1
[ 4064.913900] sas: ata7: end_device-0:0: cmd error handler
[ 4064.913984] sas: ata7: end_device-0:0: dev error handler
[ 4064.914356] sas: --- Exit sas_scsi_recover_host: busy: 0 failed: 0 tries: 1
[ 4064.915269] sr 0:0:0:0: command ffff8802fc4ccc00 timed out
[ 4064.915297] sas: Enter sas_scsi_recover_host busy: 1 failed: 1
[ 4064.915302] sas: ata7: end_device-0:0: cmd error handler
[ 4064.915382] sas: ata7: end_device-0:0: dev error handler
[ 4064.915777] sas: --- Exit sas_scsi_recover_host: busy: 0 failed: 0 tries: 1
[ 4064.923419] md: md127 stopped.
[ 4064.927256] md: bind<sdc>
[ 4064.927350] md: bind<sdb>
[ 4064.927427] md: bind<sda>
[ 4064.927505] md: bind<sdi>
[ 4065.497163] sr 0:0:0:0: command ffff880304de9700 timed out
[ 4065.497181] sas: Enter sas_scsi_recover_host busy: 1 failed: 1
[ 4065.497184] sas: ata7: end_device-0:0: cmd error handler
[ 4065.497255] sas: ata7: end_device-0:0: dev error handler
[ 4065.497650] sas: --- Exit sas_scsi_recover_host: busy: 0 failed: 0 tries: 1
[ 4065.498026] sr 0:0:0:0: command ffff8802fb703e00 timed out
[ 4065.498041] sas: Enter sas_scsi_recover_host busy: 1 failed: 1
[ 4065.498043] sas: ata7: end_device-0:0: cmd error handler
[ 4065.498106] sas: ata7: end_device-0:0: dev error handler
[ 4065.498503] sas: --- Exit sas_scsi_recover_host: busy: 0 failed: 0 tries: 1
[ 4065.499352] sr 0:0:0:0: command ffff880304de9700 timed out
[ 4065.499372] sas: Enter sas_scsi_recover_host busy: 1 failed: 1
[ 4065.499375] sas: ata7: end_device-0:0: cmd error handler
[ 4065.499483] sas: ata7: end_device-0:0: dev error handler
[ 4065.499803] sas: --- Exit sas_scsi_recover_host: busy: 0 failed: 0 tries: 1
[ 4071.294317] md: md126 stopped.
[ 4071.294421] md: bind<sdi>
[ 4071.294481] md: bind<sda>
[ 4071.294533] md: bind<sdb>
[ 4071.294596] md: bind<sdc>
[ 4071.296579] md/raid:md126: not clean -- starting background reconstruction
[ 4071.296595] md/raid:md126: device sdc operational as raid disk 0
[ 4071.296596] md/raid:md126: device sdb operational as raid disk 1
[ 4071.296597] md/raid:md126: device sda operational as raid disk 2
[ 4071.296598] md/raid:md126: device sdi operational as raid disk 3
[ 4071.296900] md/raid:md126: allocated 0kB
[ 4071.296920] md/raid:md126: raid level 5 active with 4 out of 4 devices, algorithm 0
[ 4071.296922] RAID conf printout:
[ 4071.296923] --- level:5 rd:4 wd:4
[ 4071.296925] disk 0, o:1, dev:sdc
[ 4071.296926] disk 1, o:1, dev:sdb
[ 4071.296927] disk 2, o:1, dev:sda
[ 4071.296929] disk 3, o:1, dev:sdi
[ 4071.296944] md126: detected capacity change from 0 to 18003515146240
[ 4071.297632] md126: unknown partition table
[ 4072.773368] md: md126 switched to read-write mode.
[ 4072.773686] md: resync of RAID array md126
[ 4072.773690] md: minimum _guaranteed_ speed: 1000 KB/sec/disk.
[ 4072.773692] md: using maximum available idle IO bandwidth (but not more than 200000 KB/sec) for resync.
[ 4072.773698] md: using 128k window, over a total of 5860519424k.