我们有一台 Synology NAS，2 个磁盘中的一个崩溃了，尽管智能已通过，数据完好无损。请注意，虽然磁盘不在 raid 中，但几年前我们选择了 SHR，显然 Synology 考虑了 1 个磁盘 raid。
我们先行取出崩溃的磁盘并更换它，现在我们想要恢复数据。我们将磁盘放在 debian 10 盒子里。
按照许多指南，我们设法重新创建了一个磁盘 raid，但仍然无法安装它，因为 debian 无法识别 fs。首先将磁盘放在 windows pc 上，我们发现 synology 将其格式化为三个部分，第一个是带有元数据的 ext4，我想因为我们可以看到文件夹结构，第二个和第三个包含所有数据，是 RAW。
在 debian 上采取的措施：
lsblk
sdc 8:32 0 2.7T 0 disk
├─sdc1 8:33 0 2.4G 0 part
├─sdc2 8:34 0 2G 0 part
├─sdc3 8:35 0 2.7T 0 part
cat /proc/mdstat
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]
md127 : inactive sdc3[0](S)
2925444560 blocks super 1.2
unused devices: <none>
如果我们不让它活跃起来，我猜安装就没有意义：
mdadm -Asf
mdadm: No arrays found in config file or automatically
mdadm -A /dev/md127
mdadm: /dev/md127 not identified in config file.
/etc/mdadm/mdadm.conf 中缺少某些内容：
mdadm --detail --scan
INACTIVE-ARRAY /dev/md127 metadata=1.2 name=DiskStation:2 UUID=51fe32e5:d1a74bf2:7c07fbd0:ce554944
和
mdadm --examine --scan >> /etc/mdadm/mdadm.conf
ARRAY /dev/md/2 metadata=1.2 UUID=51fe32e5:d1a74bf2:7c07fbd0:ce554944 name=DiskStation:2
我不知道为什么第二个命令输出不存在的 /dev/md/2，但是我进入 mdadm.conf 并将其替换为 md127.所以现在的配置是：
# This configuration was auto-generated on Sat, 02 Nov 2019 20:42:28 +0200 by mkconf
ARRAY /dev/md127 metadata=1.2 UUID=51fe32e5:d1a74bf2:7c07fbd0:ce554944 name=DiskStation:2
我重新启动了机器，然后执行以下操作：
mdadm --stop /dev/md127
mdadm: stopped /dev/md127
否则显然如果你尝试构建/组装突袭它会说sdc3正忙。然后我做了：
mdadm --build /dev/md127 --force --level=1 --raid-devices=1 /dev/sdc
mdadm: array /dev/md127 built and started.
cat /proc/mdstat
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]
md127 : active raid1 sdc[0]
2930266584 blocks super non-persistent [1/1] [U]
unused devices: <none>
这就是进步。但是它仍然无法识别 fs 来安装磁盘。新的 lsblk：
sdc 8:32 0 2.7T 0 disk
├─sdc1 8:33 0 2.4G 0 part
├─sdc2 8:34 0 2G 0 part
├─sdc3 8:35 0 2.7T 0 part
└─md127 9:127 0 2.7T 0 raid1
├─md127p1 259:0 0 2.4G 0 part
├─md127p2 259:1 0 2G 0 part
└─md127p3 259:2 0 2.7T 0 part
现在我尝试挂载到一个目录：
mount /dev/md127 /mnt/oldsynology/ -o ro
mount: /mnt/oldsynology: wrong fs type, bad option, bad superblock on /dev/md127, missing codepage or helper program, or other error.
mount /dev/md127p3 /mnt/oldsynology/ -o ro
mount: /mnt/oldsynology: unknown filesystem type 'linux_raid_member'.
mount /dev/sdc /mnt/oldsynology/ -o ro
mount: /mnt/oldsynology: /dev/sdc already mounted or mount point busy.
mount /dev/sdc3 /mnt/oldsynology/ -o ro
mount: /mnt/oldsynology: unknown filesystem type 'linux_raid_member'.
我也尝试使用 mount -t ext4 执行上述挂载命令，结果相同。
尽管当我将驱动器重新安装到 Synology 中时，我的 smartctl 仍可以毫无问题地读取数据。
smartctl -a /dev/sdc3
smartctl 7.1 2019-12-30 r5022 [x86_64-linux-5.3.13-1-pve] (local build)
Copyright (C) 2002-19, Bruce Allen, Christian Franke, www.smartmontools.org
=== START OF INFORMATION SECTION ===
Model Family: Western Digital Red
Device Model: WDC WD30EFRX-68EUZN0
Serial Number: WD-WCC4N2ELDDTF
LU WWN Device Id: 5 0014ee 20cc90c0c
Firmware Version: 82.00A82
User Capacity: 3,000,592,982,016 bytes [3.00 TB]
Sector Sizes: 512 bytes logical, 4096 bytes physical
Rotation Rate: 5400 rpm
Device is: In smartctl database [for details use: -P show]
ATA Version is: ACS-2 (minor revision not indicated)
SATA Version is: SATA 3.0, 6.0 Gb/s (current: 3.0 Gb/s)
Local Time is: Tue Jun 30 23:53:12 2020 EEST
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: ( 0) The previous self-test routine completed
without error or no self-test has ever
been run.
Total time to complete Offline
data collection: (38880) seconds.
Offline data collection
capabilities: (0x7b) SMART execute Offline immediate.
Auto Offline data collection on/off support.
Suspend Offline collection upon new
command.
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: ( 2) minutes.
Extended self-test routine
recommended polling time: ( 390) minutes.
Conveyance self-test routine
recommended polling time: ( 5) minutes.
SCT capabilities: (0x703d) SCT Status supported.
SCT Error Recovery Control supported.
SCT Feature Control supported.
SCT Data Table supported.
SMART Attributes Data Structure revision number: 16
Vendor Specific SMART Attributes with Thresholds:
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 - 37389
3 Spin_Up_Time 0x0027 170 170 021 Pre-fail Always - 6466
4 Start_Stop_Count 0x0032 100 100 000 Old_age Always - 33
5 Reallocated_Sector_Ct 0x0033 200 200 140 Pre-fail Always - 16
7 Seek_Error_Rate 0x002e 200 200 000 Old_age Always - 0
9 Power_On_Hours 0x0032 050 050 000 Old_age Always - 36983
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 - 32
192 Power-Off_Retract_Count 0x0032 200 200 000 Old_age Always - 22
193 Load_Cycle_Count 0x0032 200 200 000 Old_age Always - 670
194 Temperature_Celsius 0x0022 105 104 000 Old_age Always - 45
196 Reallocated_Event_Count 0x0032 186 186 000 Old_age Always - 14
197 Current_Pending_Sector 0x0032 199 199 000 Old_age Always - 529
198 Offline_Uncorrectable 0x0030 100 253 000 Old_age Offline - 0
199 UDMA_CRC_Error_Count 0x0032 200 200 000 Old_age Always - 0
200 Multi_Zone_Error_Rate 0x0008 200 200 000 Old_age Offline - 1
SMART Error Log Version: 1
No Errors Logged
SMART Self-test log structure revision number 1
Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error
# 1 Extended offline Interrupted (host reset) 90% 36677 -
# 2 Short offline Interrupted (host reset) 10% 36671 -
# 3 Extended offline Interrupted (host reset) 10% 36626 -
# 4 Extended offline Completed: read failure 10% 35995 30655688
# 5 Extended offline Interrupted (host reset) 10% 35289 -
# 6 Extended offline Interrupted (host reset) 10% 34262 -
# 7 Extended offline Interrupted (host reset) 10% 33403 -
# 8 Extended offline Interrupted (host reset) 90% 33174 -
# 9 Extended offline Interrupted (host reset) 10% 33097 -
#10 Extended offline Interrupted (host reset) 10% 33000 -
#11 Extended offline Interrupted (host reset) 10% 32792 -
#12 Extended offline Interrupted (host reset) 10% 32593 -
#13 Extended offline Completed: read failure 10% 32350 30655688
#14 Extended offline Completed: read failure 10% 28883 30655688
#15 Extended offline Interrupted (host reset) 60% 27995 -
#16 Extended offline Completed without error 00% 27835 -
#17 Extended offline Completed without error 00% 27676 -
#18 Extended offline Completed without error 00% 27508 -
#19 Extended offline Completed without error 00% 27334 -
#20 Extended offline Completed without error 00% 27167 -
#21 Extended offline Completed without error 00% 26999 -
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.
我希望有人能解答这个难题。到目前为止还没有在任何类似的帖子中找到解决方案，每个案例中总是存在略微不同的变量。
答案1
这说明：
mount /dev/md127p3 /mnt/oldsynology/ -o ro
mount: /mnt/oldsynology: unknown filesystem type 'linux_raid_member'.
看起来它/dev/md127p3本身包含另一个数组，您可以使用它来发现它mdadm -E /dev/md127p3。
也就是说，在 Linux 机器上使用 SHR 之前，我会简单地尝试克隆磁盘并将其插入原始 DiskStation。