Linux
使用陣列外的 2 個磁碟恢復 RAID5
我不想以反複試驗的方式來解決這個問題，因為我知道如果我想失去我的數據，這是最好的做法。
我在 Ubuntu 14.04 上有一台RAID5 中 4*2TB 磁碟的伺服器（是的，我知道這不明智）。
我的大部分數據都在
/homeRAID 5 和/RAID1 上。我在救援模式下啟動了伺服器，但我不知道：
- 如果問題是軟體或硬體問題，
- 如果有辦法重新掛載 RAID 以恢復這些數據。
我仔細閱讀了Recovering a failed software RAID (raid.wiki.kernel.org)，但由於我對自己的診斷不是很自信，所以我想對正在發生的事情以及如何繼續進行一些謹慎的判斷如果有什麼事要做……
我嘗試的唯一方法是安裝未安裝的 mds 設備，該設備適用於 md2
mount /dev/md2 /mnt/，但我無法安裝 md0 和 md3 ，正如我被告知的那樣/dev/md3: can't read superblock。到目前為止，這是我檢查的：
編輯分開-l
root@rescue:/mnt# parted -l Model: ATA ST2000DM001-1CH1 (scsi) Disk /dev/sda: 2000GB Sector size (logical/physical): 512B/4096B Partition Table: gpt Disk Flags: Number Start End Size File system Name Flags 1 20.5kB 1049kB 1029kB primary bios_grub 2 2097kB 10.5GB 10.5GB ext4 primary raid 3 10.5GB 2000GB 1989GB primary raid 4 2000GB 2000GB 536MB linux-swap(v1) primary Model: ATA ST2000DM001-1CH1 (scsi) Disk /dev/sdb: 2000GB Sector size (logical/physical): 512B/4096B Partition Table: gpt Disk Flags: Number Start End Size File system Name Flags 1 20.5kB 1049kB 1029kB primary bios_grub 2 2097kB 10.5GB 10.5GB ext4 primary raid 3 10.5GB 2000GB 1989GB primary raid 4 2000GB 2000GB 536MB linux-swap(v1) primary Error: /dev/sdc: unrecognised disk label Model: ATA ST2000DM001-1CH1 (scsi) Disk /dev/sdc: 2000GB Sector size (logical/physical): 512B/4096B Partition Table: unknown Disk Flags: Model: ATA ST2000DM001-1CH1 (scsi) Disk /dev/sdd: 2000GB Sector size (logical/physical): 512B/4096B Partition Table: gpt Disk Flags: Number Start End Size File system Name Flags 1 20.5kB 1049kB 1029kB primary bios_grub 2 2097kB 10.5GB 10.5GB ext4 primary raid 3 10.5GB 2000GB 1989GB primary raid 4 2000GB 2000GB 536MB linux-swap(v1) primary Model: Linux Software RAID Array (md) Disk /dev/md2: 10.5GB Sector size (logical/physical): 512B/4096B Partition Table: loop Disk Flags: Number Start End Size File system Flags 1 0.00B 10.5GB 10.5GB ext4 Error: /dev/md127: unrecognised disk label Model: Linux Software RAID Array (md) Disk /dev/md127: 10.5GB Sector size (logical/physical): 512B/4096B Partition Table: unknown Disk Flags:智能控制
root@rescue:~# smartctl -a -d ata /dev/sdc smartctl 5.41 2011-06-09 r3365 [x86_64-linux-3.10.23-xxxx-std-ipv6-64-rescue] (local build) Copyright (C) 2002-11 by Bruce Allen, http://smartmontools.sourceforge.net Smartctl: Device Read Identity Failed: Input/output error A mandatory SMART command failed: exiting. To continue, add one or more '-T permissive' options. root@rescue:~# smartctl -a -d ata /dev/sdd smartctl 5.41 2011-06-09 r3365 [x86_64-linux-3.10.23-xxxx-std-ipv6-64-rescue] (local build) Copyright (C) 2002-11 by Bruce Allen, http://smartmontools.sourceforge.net === START OF INFORMATION SECTION === Model Family: Seagate Barracuda 7200.14 (AF) Device Model: ST2000DM001-1CH164 Serial Number: W1E1KX59 LU WWN Device Id: 5 000c50 05c821593 Firmware Version: CC43 User Capacity: 2,000,398,934,016 bytes [2.00 TB] Sector Sizes: 512 bytes logical, 4096 bytes physical Device is: In smartctl database [for details use: -P show] ATA Version is: 8 ATA Standard is: ATA-8-ACS revision 4 Local Time is: Tue Dec 30 16:04:49 2014 CET SMART support is: Available - device has SMART capability. SMART support is: Enabled === START OF READ SMART DATA SECTION === SMART overall-health self-assessment test result: PASSED General SMART Values: Offline data collection status: (0x00) Offline data collection activity was never started. Auto Offline Data Collection: Disabled. Self-test execution status: ( 121) The previous self-test completed having the read element of the test failed. Total time to complete Offline data collection: ( 584) seconds. Offline data collection capabilities: (0x73) SMART execute Offline immediate. Auto Offline data collection on/off support. Suspend Offline collection upon new command. No Offline surface scan supported. Self-test supported. Conveyance Self-test supported. Selective Self-test supported. SMART capabilities: (0x0003) Saves SMART data before entering power-saving mode. Supports SMART auto save timer. Error logging capability: (0x01) Error logging supported. General Purpose Logging supported. Short self-test routine recommended polling time: ( 1) minutes. Extended self-test routine recommended polling time: ( 230) minutes. Conveyance self-test routine recommended polling time: ( 2) minutes. SCT capabilities: (0x3085) SCT Status supported. SMART Attributes Data Structure revision number: 10 Vendor Specific SMART Attributes with Thresholds: ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 1 Raw_Read_Error_Rate 0x000f 111 099 006 Pre-fail Always - 120551532 3 Spin_Up_Time 0x0003 095 095 000 Pre-fail Always - 0 4 Start_Stop_Count 0x0032 100 100 020 Old_age Always - 32 5 Reallocated_Sector_Ct 0x0033 097 097 036 Pre-fail Always - 4008 7 Seek_Error_Rate 0x000f 077 060 030 Pre-fail Always - 4351310995 9 Power_On_Hours 0x0032 079 079 000 Old_age Always - 18725 10 Spin_Retry_Count 0x0013 100 100 097 Pre-fail Always - 0 12 Power_Cycle_Count 0x0032 100 100 020 Old_age Always - 32 183 Runtime_Bad_Block 0x0032 100 100 000 Old_age Always - 0 184 End-to-End_Error 0x0032 100 100 099 Old_age Always - 0 187 Reported_Uncorrect 0x0032 089 089 000 Old_age Always - 11 188 Command_Timeout 0x0032 100 100 000 Old_age Always - 0 0 0 189 High_Fly_Writes 0x003a 100 100 000 Old_age Always - 0 190 Airflow_Temperature_Cel 0x0022 068 056 045 Old_age Always - 32 (Min/Max 26/35) 191 G-Sense_Error_Rate 0x0032 100 100 000 Old_age Always - 0 192 Power-Off_Retract_Count 0x0032 100 100 000 Old_age Always - 31 193 Load_Cycle_Count 0x0032 100 100 000 Old_age Always - 46 194 Temperature_Celsius 0x0022 032 044 000 Old_age Always - 32 (0 16 0 0) 197 Current_Pending_Sector 0x0012 082 082 000 Old_age Always - 3056 198 Offline_Uncorrectable 0x0010 082 082 000 Old_age Offline - 3056 199 UDMA_CRC_Error_Count 0x003e 200 200 000 Old_age Always - 0 240 Head_Flying_Hours 0x0000 100 253 000 Old_age Offline - 18708h+109m+27.415s 241 Total_LBAs_Written 0x0000 100 253 000 Old_age Offline - 24242600022 242 Total_LBAs_Read 0x0000 100 253 000 Old_age Offline - 112149279703 SMART Error Log Version: 1 ATA Error Count: 11 (device log contains only the most recent five errors) CR = Command Register [HEX] FR = Features Register [HEX] SC = Sector Count Register [HEX] SN = Sector Number Register [HEX] CL = Cylinder Low Register [HEX] CH = Cylinder High Register [HEX] DH = Device/Head Register [HEX] DC = Device Command Register [HEX] ER = Error register [HEX] ST = Status register [HEX] Powered_Up_Time is measured from power on, and printed as DDd+hh:mm:SS.sss where DD=days, hh=hours, mm=minutes, SS=sec, and sss=millisec. It "wraps" after 49.710 days. Error 11 occurred at disk power-on lifetime: 18520 hours (771 days + 16 hours) When the command that caused the error occurred, the device was active or idle. After command completion occurred, registers were: ER ST SC SN CL CH DH -- -- -- -- -- -- -- 40 51 00 ff ff ff 0f Error: UNC at LBA = 0x0fffffff = 268435455 Commands leading to the command that caused the error were: CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name -- -- -- -- -- -- -- -- ---------------- -------------------- 60 00 08 ff ff ff 4f 00 09:32:13.900 READ FPDMA QUEUED ef 10 02 00 00 00 a0 00 09:32:13.898 SET FEATURES [Reserved for Serial ATA] 27 00 00 00 00 00 e0 00 09:32:13.898 READ NATIVE MAX ADDRESS EXT ec 00 00 00 00 00 a0 00 09:32:13.898 IDENTIFY DEVICE ef 03 46 00 00 00 a0 00 09:32:13.898 SET FEATURES [Set transfer mode] Error 10 occurred at disk power-on lifetime: 18520 hours (771 days + 16 hours) When the command that caused the error occurred, the device was active or idle. After command completion occurred, registers were: ER ST SC SN CL CH DH -- -- -- -- -- -- -- 40 51 00 ff ff ff 0f Error: UNC at LBA = 0x0fffffff = 268435455 Commands leading to the command that caused the error were: CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name -- -- -- -- -- -- -- -- ---------------- -------------------- 60 00 08 ff ff ff 4f 00 09:32:10.764 READ FPDMA QUEUED 60 00 08 ff ff ff 4f 00 09:32:10.763 READ FPDMA QUEUED 60 00 38 ff ff ff 4f 00 09:32:10.763 READ FPDMA QUEUED ef 10 02 00 00 00 a0 00 09:32:10.763 SET FEATURES [Reserved for Serial ATA] 27 00 00 00 00 00 e0 00 09:32:10.763 READ NATIVE MAX ADDRESS EXT Error 9 occurred at disk power-on lifetime: 18520 hours (771 days + 16 hours) When the command that caused the error occurred, the device was active or idle. After command completion occurred, registers were: ER ST SC SN CL CH DH -- -- -- -- -- -- -- 40 51 00 ff ff ff 0f Error: UNC at LBA = 0x0fffffff = 268435455 Commands leading to the command that caused the error were: CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name -- -- -- -- -- -- -- -- ---------------- -------------------- 60 00 38 ff ff ff 4f 00 09:32:09.084 READ FPDMA QUEUED 61 00 08 00 88 38 41 00 09:32:07.445 WRITE FPDMA QUEUED 60 00 08 ff ff ff 4f 00 09:32:07.416 READ FPDMA QUEUED 60 00 08 ff ff ff 4f 00 09:32:07.416 READ FPDMA QUEUED 60 00 08 ff ff ff 4f 00 09:32:07.416 READ FPDMA QUEUED Error 8 occurred at disk power-on lifetime: 18520 hours (771 days + 16 hours) When the command that caused the error occurred, the device was active or idle. After command completion occurred, registers were: ER ST SC SN CL CH DH -- -- -- -- -- -- -- 40 51 00 ff ff ff 0f Error: WP at LBA = 0x0fffffff = 268435455 Commands leading to the command that caused the error were: CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name -- -- -- -- -- -- -- -- ---------------- -------------------- 61 00 40 ff ff ff 4f 00 09:32:04.118 WRITE FPDMA QUEUED 61 00 08 70 88 38 41 00 09:32:04.117 WRITE FPDMA QUEUED 61 00 40 ff ff ff 4f 00 09:32:04.117 WRITE FPDMA QUEUED 60 00 40 ff ff ff 4f 00 09:32:04.117 READ FPDMA QUEUED 60 00 08 ff ff ff 4f 00 09:32:04.117 READ FPDMA QUEUED Error 7 occurred at disk power-on lifetime: 17319 hours (721 days + 15 hours) When the command that caused the error occurred, the device was active or idle. After command completion occurred, registers were: ER ST SC SN CL CH DH -- -- -- -- -- -- -- 40 51 00 50 a9 59 02 Error: UNC at LBA = 0x0259a950 = 39430480 Commands leading to the command that caused the error were: CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name -- -- -- -- -- -- -- -- ---------------- -------------------- 60 00 00 00 aa 59 42 00 01:31:02.054 READ FPDMA QUEUED 60 00 00 00 a6 59 42 00 01:31:02.054 READ FPDMA QUEUED 60 00 00 00 92 36 42 00 01:30:55.032 READ FPDMA QUEUED 60 00 00 00 86 36 42 00 01:30:51.600 READ FPDMA QUEUED 60 00 00 00 82 36 42 00 01:30:51.593 READ FPDMA QUEUED SMART Self-test log structure revision number 1 Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error # 1 Extended offline Completed: read failure 90% 18706 3848494344 # 2 Short offline Completed without error 00% 3481 - # 3 Short offline Completed without error 00% 3472 - # 4 Short offline Completed without error 00% 3472 - # 5 Short offline Completed without error 00% 13 - # 6 Short offline Completed without error 00% 5 - # 7 Short offline Completed without error 00% 5 - # 8 Short offline Completed without error 00% 0 - SMART Selective self-test log data structure revision number 1 SPAN MIN_LBA MAX_LBA CURRENT_TEST_STATUS 1 0 0 Not_testing 2 0 0 Not_testing 3 0 0 Not_testing 4 0 0 Not_testing 5 0 0 Not_testing Selective self-test flags (0x0): After scanning selected spans, do NOT read-scan remainder of disk. If Selective self-test is pending on power-up, resume after 0 minute delay.ls /dev
ls /dev MAKEDEV md0 ptya0 ptyc5 ptyea ptyqf ptyt4 ptyv9 ptyxe ram11 sg1 tty34 ttyS1 ttyc2 ttye7 ttyqc ttyt1 ttyv6 ttyxb urandom aer_inject md127 ptya1 ptyc6 ptyeb ptyr0 ptyt5 ptyva ptyxf ram12 sg2 tty35 ttyS2 ttyc3 ttye8 ttyqd ttyt2 ttyv7 ttyxc vcs autofs md2 ptya2 ptyc7 ptyec ptyr1 ptyt6 ptyvb ptyy0 ram13 sg3 tty36 ttyS3 ttyc4 ttye9 ttyqe ttyt3 ttyv8 ttyxd vcs1 block md3 ptya3 ptyc8 ptyed ptyr2 ptyt7 ptyvc ptyy1 ram14 shm tty37 ttya0 ttyc5 ttyea ttyqf ttyt4 ttyv9 ttyxe vcs2 […]貓 /proc/mdstat
cat /proc/mdstat Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4] [multipath] [faulty] md127 : active raid1 sdc2[2] 10238912 blocks [4/1] [__U_] md2 : active raid1 sdd2[3] sda2[0] sdb2[1] 10238912 blocks [4/3] [UU_U]mdadm –detail
root@rescue:~# mdadm --detail /dev/md2 /dev/md2: Version : 0.90 Creation Time : Tue Sep 2 16:46:34 2014 Raid Level : raid1 Array Size : 10238912 (9.76 GiB 10.48 GB) Used Dev Size : 10238912 (9.76 GiB 10.48 GB) Raid Devices : 4 Total Devices : 3 Preferred Minor : 2 Persistence : Superblock is persistent Update Time : Sat Dec 27 17:31:03 2014 State : clean, degraded Active Devices : 3 Working Devices : 3 Failed Devices : 0 Spare Devices : 0 UUID : 5a33c710:006f668d:a4d2adc2:26fd5302 (local to host rescue.ovh.net) Events : 0.503145 Number Major Minor RaidDevice State 0 8 2 0 active sync /dev/sda2 1 8 18 1 active sync /dev/sdb2 2 0 0 2 removed 3 8 50 3 active sync /dev/sdd2 root@rescue:~# mdadm --detail /dev/md127 /dev/md127: Version : 0.90 Creation Time : Tue Sep 2 16:46:34 2014 Raid Level : raid1 Array Size : 10238912 (9.76 GiB 10.48 GB) Used Dev Size : 10238912 (9.76 GiB 10.48 GB) Raid Devices : 4 Total Devices : 1 Preferred Minor : 127 Persistence : Superblock is persistent Update Time : Sat Dec 27 17:31:16 2014 State : clean, degraded Active Devices : 1 Working Devices : 1 Failed Devices : 0 Spare Devices : 0 Number Major Minor RaidDevice State 0 0 0 0 removed 1 0 0 1 removed 2 8 34 2 active sync /dev/sdc2 3 0 0 3 removed最後 mdadm –examine sd*
root@rescue:~# mdadm --examine /dev/sd* /dev/sda: MBR Magic : aa55 Partition[0] : 3907029167 sectors at 1 (type ee) mdadm: No md superblock detected on /dev/sda1. /dev/sda2: Magic : a92b4efc Version : 0.90.00 UUID : 5a33c710:006f668d:a4d2adc2:26fd5302 (local to host rescue.ovh.net) Creation Time : Tue Sep 2 16:46:34 2014 Raid Level : raid1 Used Dev Size : 10238912 (9.76 GiB 10.48 GB) Array Size : 10238912 (9.76 GiB 10.48 GB) Raid Devices : 4 Total Devices : 3 Preferred Minor : 2 Update Time : Sat Dec 27 18:20:56 2014 State : clean Active Devices : 3 Working Devices : 3 Failed Devices : 1 Spare Devices : 0 Checksum : 78eed7b8 - correct Events : 503147 Number Major Minor RaidDevice State this 0 8 2 0 active sync /dev/sda2 0 0 8 2 0 active sync /dev/sda2 1 1 8 18 1 active sync /dev/sdb2 2 2 0 0 2 faulty removed 3 3 8 50 3 active sync /dev/sdd2 /dev/sda3: Magic : a92b4efc Version : 0.90.00 UUID : 4a417350:7192f812:a4d2adc2:26fd5302 (local to host rescue.ovh.net) Creation Time : Tue Sep 2 16:46:35 2014 Raid Level : raid5 Used Dev Size : 1942745600 (1852.75 GiB 1989.37 GB) Array Size : 5828236800 (5558.24 GiB 5968.11 GB) Raid Devices : 4 Total Devices : 3 Preferred Minor : 3 Update Time : Mon Dec 22 10:33:05 2014 State : clean Active Devices : 2 Working Devices : 2 Failed Devices : 2 Spare Devices : 0 Checksum : 4d44c428 - correct Events : 109608 Layout : left-symmetric Chunk Size : 512K Number Major Minor RaidDevice State this 0 8 3 0 active sync /dev/sda3 0 0 8 3 0 active sync /dev/sda3 1 1 8 19 1 active sync /dev/sdb3 2 2 0 0 2 faulty removed 3 3 0 0 3 faulty removed mdadm: No md superblock detected on /dev/sda4. /dev/sdb: MBR Magic : aa55 Partition[0] : 3907029167 sectors at 1 (type ee) mdadm: No md superblock detected on /dev/sdb1. /dev/sdb2: Magic : a92b4efc Version : 0.90.00 UUID : 5a33c710:006f668d:a4d2adc2:26fd5302 (local to host rescue.ovh.net) Creation Time : Tue Sep 2 16:46:34 2014 Raid Level : raid1 Used Dev Size : 10238912 (9.76 GiB 10.48 GB) Array Size : 10238912 (9.76 GiB 10.48 GB) Raid Devices : 4 Total Devices : 3 Preferred Minor : 2 Update Time : Sat Dec 27 18:20:56 2014 State : clean Active Devices : 3 Working Devices : 3 Failed Devices : 1 Spare Devices : 0 Checksum : 78eed7ca - correct Events : 503147 Number Major Minor RaidDevice State this 1 8 18 1 active sync /dev/sdb2 0 0 8 2 0 active sync /dev/sda2 1 1 8 18 1 active sync /dev/sdb2 2 2 0 0 2 faulty removed 3 3 8 50 3 active sync /dev/sdd2 /dev/sdb3: Magic : a92b4efc Version : 0.90.00 UUID : 4a417350:7192f812:a4d2adc2:26fd5302 (local to host rescue.ovh.net) Creation Time : Tue Sep 2 16:46:35 2014 Raid Level : raid5 Used Dev Size : 1942745600 (1852.75 GiB 1989.37 GB) Array Size : 5828236800 (5558.24 GiB 5968.11 GB) Raid Devices : 4 Total Devices : 3 Preferred Minor : 3 Update Time : Mon Dec 22 10:33:05 2014 State : clean Active Devices : 2 Working Devices : 2 Failed Devices : 2 Spare Devices : 0 Checksum : 4d44c43a - correct Events : 109608 Layout : left-symmetric Chunk Size : 512K Number Major Minor RaidDevice State this 1 8 19 1 active sync /dev/sdb3 0 0 8 3 0 active sync /dev/sda3 1 1 8 19 1 active sync /dev/sdb3 2 2 0 0 2 faulty removed 3 3 0 0 3 faulty removed mdadm: No md superblock detected on /dev/sdb4. mdadm: No md superblock detected on /dev/sdc. mdadm: No md superblock detected on /dev/sdc1. mdadm: No md superblock detected on /dev/sdc2. mdadm: No md superblock detected on /dev/sdc3. mdadm: No md superblock detected on /dev/sdc4. /dev/sdd: MBR Magic : aa55 Partition[0] : 3907029167 sectors at 1 (type ee) mdadm: No md superblock detected on /dev/sdd1. /dev/sdd2: Magic : a92b4efc Version : 0.90.00 UUID : 5a33c710:006f668d:a4d2adc2:26fd5302 (local to host rescue.ovh.net) Creation Time : Tue Sep 2 16:46:34 2014 Raid Level : raid1 Used Dev Size : 10238912 (9.76 GiB 10.48 GB) Array Size : 10238912 (9.76 GiB 10.48 GB) Raid Devices : 4 Total Devices : 3 Preferred Minor : 2 Update Time : Sat Dec 27 18:20:56 2014 State : clean Active Devices : 3 Working Devices : 3 Failed Devices : 1 Spare Devices : 0 Checksum : 78eed7ee - correct Events : 503147 Number Major Minor RaidDevice State this 3 8 50 3 active sync /dev/sdd2 0 0 8 2 0 active sync /dev/sda2 1 1 8 18 1 active sync /dev/sdb2 2 2 0 0 2 faulty removed 3 3 8 50 3 active sync /dev/sdd2 /dev/sdd3: Magic : a92b4efc Version : 0.90.00 UUID : 4a417350:7192f812:a4d2adc2:26fd5302 (local to host rescue.ovh.net) Creation Time : Tue Sep 2 16:46:35 2014 Raid Level : raid5 Used Dev Size : 1942745600 (1852.75 GiB 1989.37 GB) Array Size : 5828236800 (5558.24 GiB 5968.11 GB) Raid Devices : 4 Total Devices : 3 Preferred Minor : 3 Update Time : Mon Dec 22 01:55:55 2014 State : active Active Devices : 3 Working Devices : 3 Failed Devices : 1 Spare Devices : 0 Checksum : 4d429eeb - correct Events : 109599 Layout : left-symmetric Chunk Size : 512K Number Major Minor RaidDevice State this 3 8 51 3 active sync /dev/sdd3 0 0 8 3 0 active sync /dev/sda3 1 1 8 19 1 active sync /dev/sdb3 2 2 0 0 2 faulty removed 3 3 8 51 3 active sync /dev/sdd3 mdadm: No md superblock detected on /dev/sdd4.編輯
在最後一次嘗試中，我解除安裝了 /dev/md2 並使用 mdadm 停止了它。
然後我能夠組裝/dev/md3：
mdadm --assemble --force /dev/md3 /dev/sd[abd]3 mdadm: forcing event count in /dev/sdd3(3) from 109599 upto 109608 mdadm: clearing FAULTY flag for device 2 in /dev/md3 for /dev/sdd3 mdadm: Marking array /dev/md3 as 'clean' mdadm: /dev/md3 has been started with 3 drives (out of 4).當時的系統日誌：
md/raid:md3: device sda3 operational as raid disk 0 md/raid:md3: device sdd3 operational as raid disk 3 md/raid:md3: device sdb3 operational as raid disk 1 md/raid:md3: allocated 4338kB md/raid:md3: raid level 5 active with 3 out of 4 devices, algorithm 2 RAID conf printout: --- level:5 rd:4 wd:3 disk 0, o:1, dev:sda3 disk 1, o:1, dev:sdb3 disk 3, o:1, dev:sdd3 md3: detected capacity change from 0 to 5968114483200 md3: unknown partition tableRAID 似乎還可以：
root@rescue:/mnt# cat /proc/mdstat Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4] [multipath] [faulty] md3 : active raid5 sda3[0] sdd3[3] sdb3[1] 5828236800 blocks level 5, 512k chunk, algorithm 2 [4/3] [UU_U] […]但我無法安裝它：
root@rescue:/mnt# mount /dev/md3 /mnt/home mount: wrong fs type, bad option, bad superblock on /dev/md3, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so這樣做時，系統日誌中出現了許多錯誤：
ata4.00: exception Emask 0x0 SAct 0xfe SErr 0x0 action 0x0 ata4.00: irq_stat 0x40000008 ata4.00: failed command: READ FPDMA QUEUED ata4.00: cmd 60/18:08:18:34:63/00:00:e5:00:00/40 tag 1 ncq 12288 in res 41/40:18:18:34:63/00:00:e5:00:00/00 Emask 0x409 (media error) <F> ata4.00: status: { DRDY ERR } ata4.00: error: { UNC } ata4.00: configured for UDMA/133 sd 3:0:0:0: [sdd] Unhandled sense code sd 3:0:0:0: [sdd] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE sd 3:0:0:0: [sdd] 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 e5 63 34 18 sd 3:0:0:0: [sdd] Add. Sense: Unrecovered read error - auto reallocate failed sd 3:0:0:0: [sdd] CDB: Read(10): 28 00 e5 63 34 18 00 00 18 00 blk_update_request: 46 callbacks suppressed end_request: I/O error, dev sdd, sector 3848483864 md/raid:md3: read error not correctable (sector 3828001816 on sdd3). md/raid:md3: Disk failure on sdd3, disabling device.我試圖糾正它們，
hdparm但它們太多了，每次出現一堆新的。顯然，正如係統日誌中提到的，
md/raid:md3: Disk failure on sdd3, disabling device.在我嘗試掛載 md3 的同時，陣列的狀態變為 FAILED。看來我已經輸掉了這場戰鬥……
如果我理解正確，您的 /dev/md3 是 raid5，應該由 /dev/sda3、/dev/sdb3、/dev/sdc3（不再存在）和 /dev/sdd3 組成。
那麼你從 mdadm –detail /dev/md3 中得到了什麼？
為什麼 /dev/sdc 似乎仍然有損壞的分區表？
即使 /dev/sdc 中的分區仍然失去，也許可以恢復您的數據，但我會嘗試以下救援操作：
1）使用一些live CD啟動，不要掛載任何分區或raid磁碟。
2）製作所有磁碟的原始映像副本，是的，您將需要超過 8 TB 的可用空間，可能在某個網路驅動器上。如果您的磁碟物理上沒有問題，您可以使用 dd 來製作副本。如果某些磁碟物理損壞，您可能必須改用某些 ddrescue 程序。
- 製作原始原始圖像副本的工作原始圖像副本，是的，您將需要另外 8 TB 的可用空間。
4）使用像qemu或virtualbox這樣的虛擬機。首先使用一些適合數據救援的優質 live CD 啟動虛擬機。Systemrescuecd 可能是一個不錯的選擇。
在虛擬機中，使用您的工作原始磁碟映像副本，嘗試修復您的工作原始磁碟映像副本。一個起點可能是將分區表添加到 /dev/sdc 的工作原始磁碟映像副本。/dev/sdc 的分區表應該和 /dev/sdd 的分區表看起來一樣。
當您認為您已經解決了問題時，從您的工作磁碟映像副本啟動您的虛擬機。
一旦您的虛擬機證明您的磁碟映像文件已被修復，將修復的映像複製回您的物理磁碟。如果某個物理磁碟損壞，您可能需要先更換它。
如果您在某個階段發現修復損壞的 RAID 的嘗試只會讓事情變得更糟，請使用原始原始磁碟映像覆蓋您正在工作的原始磁碟映像並重新啟動。