I have a SME8 server with a RAID1 configuration. About 2,5 months ago I succesfully replaced both SATA disks with two brand new Western Digital RE4 500 GB drives (device model WDC WD5003ABYX-01WERA1). This weekend I received an e-mail that both /dev/md1 and /dev/md2 failed.
The "Manage Disk Redundancy" option in the console menu looks like this:
¦ Current RAID status: ¦
¦ ¦
¦ Personalities : [raid1] ¦
¦ md1 : active raid1 sdb1[0] sda1[2](F) ¦
¦ 104320 blocks [2/1] [U_] ¦
¦ md2 : active raid1 sdb2[0] sda2[2](F) ¦
¦ 488279552 blocks [2/1] [U_] ¦
¦ unused devices: <none> ¦
¦ ¦
¦ The free disk count must equal one. ¦
¦ ¦
¦ Manual intervention may be required. ¦
¦ ¦
¦ Current disk status: ¦
¦ ¦
¦ Installed disks: sda sdb ¦
¦ Used disks: sda sdb ¦
The RAID array clearly is broken:
[root@servertje ~]# mdadm -D /dev/md1
/dev/md1:
Version : 0.90
Creation Time : Fri May 2 10:00:03 2008
Raid Level : raid1
Array Size : 104320 (101.89 MiB 106.82 MB)
Used Dev Size : 104320 (101.89 MiB 106.82 MB)
Raid Devices : 2
Total Devices : 2
Preferred Minor : 1
Persistence : Superblock is persistent
Update Time : Sun May 26 04:22:02 2013
State : clean, degraded
Active Devices : 1
Working Devices : 1
Failed Devices : 1
Spare Devices : 0
UUID : 6fb130bb:052819c9:18c985e4:efcf8909
Events : 0.5088
Number Major Minor RaidDevice State
0 8 17 0 active sync /dev/sdb1
1 0 0 1 removed
2 8 1 - faulty spare /dev/sda1
[root@servertje ~]# mdadm -D /dev/md2
/dev/md2:
Version : 0.90
Creation Time : Fri May 2 10:00:03 2008
Raid Level : raid1
Array Size : 488279552 (465.66 GiB 500.00 GB)
Used Dev Size : 488279552 (465.66 GiB 500.00 GB)
Raid Devices : 2
Total Devices : 2
Preferred Minor : 2
Persistence : Superblock is persistent
Update Time : Mon May 27 11:56:54 2013
State : clean, degraded
Active Devices : 1
Working Devices : 1
Failed Devices : 1
Spare Devices : 0
UUID : 3f977def:0340e1fe:66d22f5c:669c2be8
Events : 0.43800854
Number Major Minor RaidDevice State
0 8 18 0 active sync /dev/sdb2
1 0 0 1 removed
2 8 2 - faulty spare /dev/sda2
So, it seems sda has some serious problems. I also received some SMART warnings via e-mail (Offline uncorrectable sectors: 1 and Currently unreadable (pending) sectors: 1). I ran a short smartctl selftest and the results are not giving me any peace of mind:
[root@servertje ~]# smartctl -l selftest /dev/sda
=== START OF READ SMART DATA SECTION ===
SMART Self-test log structure revision number 1
Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error
# 1 Short offline Completed: read failure 60% 2016 216889
# 2 Short offline Completed without error 00% 192 -
# 3 Extended offline Completed without error 00% 4 -
# 4 Short offline Completed without error 00% 2 -
The "Reallocated_Sector_Ct", "Reallocated_Event_Count" and "Multi_Zone_Error_Rate" values are not looking good either:
ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE
1 Raw_Read_Error_Rate 0x002f 200 200 051 Pre-fail Always - 0
3 Spin_Up_Time 0x0027 135 132 021 Pre-fail Always - 4233
4 Start_Stop_Count 0x0032 100 100 000 Old_age Always - 42
5 Reallocated_Sector_Ct 0x0033 199 199 140 Pre-fail Always - 24
7 Seek_Error_Rate 0x002e 200 200 000 Old_age Always - 0
9 Power_On_Hours 0x0032 098 098 000 Old_age Always - 2055
10 Spin_Retry_Count 0x0032 100 253 000 Old_age Always - 0
11 Calibration_Retry_Count 0x0032 100 253 000 Old_age Always - 0
12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 40
192 Power-Off_Retract_Count 0x0032 200 200 000 Old_age Always - 12
193 Load_Cycle_Count 0x0032 200 200 000 Old_age Always - 29
194 Temperature_Celsius 0x0022 114 098 000 Old_age Always - 29
196 Reallocated_Event_Count 0x0032 176 176 000 Old_age Always - 24
197 Current_Pending_Sector 0x0032 200 200 000 Old_age Always - 1
198 Offline_Uncorrectable 0x0030 200 200 000 Old_age Offline - 1
199 UDMA_CRC_Error_Count 0x0032 200 200 000 Old_age Always - 0
200 Multi_Zone_Error_Rate 0x0008 149 149 000 Old_age Offline - 10334
Conclusion: time to ditch sda and install a brand new disk.
My plan (after reading the advice given in the wiki and some forum posts) is as follows:
1. Shutdown server
2. Disconnect and remove the faulty sda disk (connected to the SATA1 cable)
3. Disconnect the good sdb disk (connected to the SATA2 cable) and connect it to the SATA1 cable
4. Insert a brand new 500 GB disk and connect it to the SATA2 cable
5. Boot the server
6. Resynchronize the RAID in the Console > Manage Disk Redundancy panel
Is this the correct way of handling this situation?