Resync-re várva 

# lvdisplay 
  --- Logical volume ---
  LV Name                /dev/store3/nas4vol1
  VG Name                store3
  LV UUID                idtYea-c0y0-3SRY-a5Dn-QmTX-cRf1-Q6eDwh
  LV Write Access        read/write
  LV Status              available
  # open                 1
  LV Size                1.83 TB
  Current LE             59857
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:0
   
  --- Logical volume ---
  LV Name                /dev/store3/nas4vol2
  VG Name                store3
  LV UUID                iXCmgK-M30i-Ssgb-iJ2u-llOW-HR2I-lOkQRX
  LV Write Access        read/write
  LV Status              available
  # open                 1
  LV Size                1.81 TB
  Current LE             59375
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:1

Hmm, hmm.... 

sd 2:0:0:0: [sdc] 3907029168 512-byte hardware sectors (2000399 MB)
sd 2:0:0:0: [sdc] Write Protect is off
sd 2:0:0:0: [sdc] Mode Sense: 00 3a 00 00
sd 2:0:0:0: [sdc] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
ata3.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x0
ata3.00: irq_stat 0x40000008
ata3.00: cmd 60/28:00:90:ca:cf/00:00:30:00:00/40 tag 0 ncq 20480 in
         res 41/40:00:aa:ca:cf/0d:00:30:00:00/40 Emask 0x409 (media error) <F>
ata3.00: status: { DRDY ERR }
ata3.00: error: { UNC }
ata3.00: configured for UDMA/133
sd 2:0:0:0: [sdc] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE,SUGGEST_OK
sd 2:0:0:0: [sdc] Sense Key : Medium Error [current] [descriptor]
Descriptor sense data with sense descriptors (in hex):
        72 03 11 04 00 00 00 0c 00 0a 80 00 00 00 00 00 
        30 cf ca aa 
sd 2:0:0:0: [sdc] Add. Sense: Unrecovered read error - auto reallocate failed
end_request: I/O error, dev sdc, sector 818924202
ata3: EH complete
sd 2:0:0:0: [sdc] 3907029168 512-byte hardware sectors (2000399 MB)
sd 2:0:0:0: [sdc] Write Protect is off
sd 2:0:0:0: [sdc] Mode Sense: 00 3a 00 00
sd 2:0:0:0: [sdc] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
raid5:md0: read error corrected (8 sectors at 818924136 on sdc1)
raid5:md0: read error corrected (8 sectors at 818924144 on sdc1)
raid5:md0: read error corrected (8 sectors at 818924152 on sdc1)
iSCSI Enterprise Target Software - version 0.4.17-of

Mindeközben... 


# cat /proc/mdstat 
Personalities : [raid6] [raid5] [raid4] [raid10] 
md0 : active raid6 sde1[3] sdd1[2] sdc1[1] sdb1[0]
      3907023872 blocks level 6, 64k chunk, algorithm 2 [4/4] [UUUU]
      [==>..................]  resync = 13.9% (271804296/1953511936) finish=470.1min speed=59613K/sec

A nap(ok) kérdése, hogy sikerül-e végigérnie! Én szurkolok neki :) Durván két éve pörögnek folyamatosan ezek az "szerver SATA-k". Mentés megy rájuk, napi kb. egy tera.