所以最近一次停电后我的 DS718+ RAID 崩溃了。
在与 Syno 支持部门调查后，我们还发现我的 RAM 已损坏（已被移除），而且由于它不是官方支持的 RAM 模块，他们现在不再帮助我恢复我的 RAID（对此表示感谢），因为他们怀疑损坏的文件系统由此引起，而不是断电。
我确实有备份，但已经很旧了，所以如果可能的话，我想恢复一下。如果不行，我也可以恢复。
目前我可以告诉你的是：
btrfs-显示-super /dev/md2
superblock: bytenr=65536, device=/dev/md2
---------------------------------------------------------
ERROR: bad magic on superblock on /dev/md2 at 65536
fdisk -l
Disk /dev/ram0: 640 MiB, 671088640 bytes, 1310720 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/ram1: 640 MiB, 671088640 bytes, 1310720 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/ram2: 640 MiB, 671088640 bytes, 1310720 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/ram3: 640 MiB, 671088640 bytes, 1310720 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/ram4: 640 MiB, 671088640 bytes, 1310720 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/ram5: 640 MiB, 671088640 bytes, 1310720 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/ram6: 640 MiB, 671088640 bytes, 1310720 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/ram7: 640 MiB, 671088640 bytes, 1310720 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/ram8: 640 MiB, 671088640 bytes, 1310720 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/ram9: 640 MiB, 671088640 bytes, 1310720 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/ram10: 640 MiB, 671088640 bytes, 1310720 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/ram11: 640 MiB, 671088640 bytes, 1310720 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/ram12: 640 MiB, 671088640 bytes, 1310720 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/ram13: 640 MiB, 671088640 bytes, 1310720 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/ram14: 640 MiB, 671088640 bytes, 1310720 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/ram15: 640 MiB, 671088640 bytes, 1310720 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/sda: 3.7 TiB, 4000787030016 bytes, 7814037168 sectors
Disk model: WD40EFRX-68N32N0
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: B0741029-0239-4B70-BDC9-115FFE436B29
Device Start End Sectors Size Type
/dev/sda1 2048 4982527 4980480 2.4G Linux RAID
/dev/sda2 4982528 9176831 4194304 2G Linux RAID
/dev/sda5 9453280 7813830239 7804376960 3.6T Linux RAID
Disk /dev/sdb: 3.7 TiB, 4000787030016 bytes, 7814037168 sectors
Disk model: WD4003FFBX-68MU3N0
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: 7D01494F-CF7B-4DFF-8735-C9F326A16775
Device Start End Sectors Size Type
/dev/sdb1 2048 4982527 4980480 2.4G Linux RAID
/dev/sdb2 4982528 9176831 4194304 2G Linux RAID
/dev/sdb5 9453280 7813830239 7804376960 3.6T Linux RAID
Disk /dev/md0: 2.4 GiB, 2549940224 bytes, 4980352 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/zram0: 275 MiB, 288358400 bytes, 70400 sectors
Units: sectors of 1 * 4096 = 4096 bytes
Sector size (logical/physical): 4096 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/zram1: 275 MiB, 288358400 bytes, 70400 sectors
Units: sectors of 1 * 4096 = 4096 bytes
Sector size (logical/physical): 4096 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/zram2: 275 MiB, 288358400 bytes, 70400 sectors
Units: sectors of 1 * 4096 = 4096 bytes
Sector size (logical/physical): 4096 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/zram3: 275 MiB, 288358400 bytes, 70400 sectors
Units: sectors of 1 * 4096 = 4096 bytes
Sector size (logical/physical): 4096 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/md1: 2 GiB, 2147418112 bytes, 4194176 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/synoboot: 120 MiB, 125829120 bytes, 245760 sectors
Disk model: DiskStation
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: 0B6F377D-3CFE-49FF-825F-7662245E3112
Device Start End Sectors Size Type
/dev/synoboot1 2048 67583 65536 32M EFI System
/dev/synoboot2 67584 239615 172032 84M Linux filesystem
Disk /dev/md2: 3.6 TiB, 3995839758336 bytes, 7804374528 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/mapper/vg1000-lv: 3.6 TiB, 3995837923328 bytes, 7804370944 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk /dev/mapper/cachedev_0: 3.6 TiB, 3995837923328 bytes, 7804370944 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
mdadm --检查 /dev/sda5
/dev/sda5:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x0
Array UUID : 4df9f767:00c49417:945e810a:3c7ae5cf
Name : DiskStation:2
Creation Time : Thu Aug 27 16:55:24 2015
Raid Level : raid1
Raid Devices : 2
Avail Dev Size : 7804374912 (3721.42 GiB 3995.84 GB)
Array Size : 3902187264 (3721.42 GiB 3995.84 GB)
Used Dev Size : 7804374528 (3721.42 GiB 3995.84 GB)
Data Offset : 2048 sectors
Super Offset : 8 sectors
Unused Space : before=1968 sectors, after=384 sectors
State : clean
Device UUID : eeb9349e:2df293df:e3e4d149:341a8cd9
Update Time : Tue Oct 19 21:43:44 2021
Checksum : 1776634c - correct
Events : 236201
Device Role : Active device 1
Array State : AA ('A' == active, '.' == missing, 'R' == replacing)
mdadm --检查 /dev/sdb5
/dev/sdb5:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x0
Array UUID : 4df9f767:00c49417:945e810a:3c7ae5cf
Name : DiskStation:2
Creation Time : Thu Aug 27 16:55:24 2015
Raid Level : raid1
Raid Devices : 2
Avail Dev Size : 7804374912 (3721.42 GiB 3995.84 GB)
Array Size : 3902187264 (3721.42 GiB 3995.84 GB)
Used Dev Size : 7804374528 (3721.42 GiB 3995.84 GB)
Data Offset : 2048 sectors
Super Offset : 8 sectors
Unused Space : before=1968 sectors, after=384 sectors
State : clean
Device UUID : b0de0510:3424cbdd:380068fb:af4fa72d
Update Time : Tue Oct 19 21:43:44 2021
Checksum : 8d300ae5 - correct
Events : 236201
Device Role : Active device 0
Array State : AA ('A' == active, '.' == missing, 'R' == replacing)
命令dumpe2fs和文件系统检查顺便说一句，找不到-不知道为什么。
当尝试mke2fs -n /dev/md2它说：
mke2fs 1.44.1 (24-Mar-2018)
/dev/md2 contains a LVM2_member file system
Proceed anyway? (y,N) y
/dev/md2 is apparently in use by the system; will not make a filesystem here!
我已经有将近两周没有使用数据/NAS 了，所以任何帮助我都非常感谢。由于我不是 Linux 爱好者，所以我很感激直接的建议。我知道 sda5 和 sdb5 是我的两个磁盘，md2 是 RAID。但不确定 LVM2_member 是什么，也不知道我现在如何修复它——如果可能的话。
编辑：
mdadm --assemble --scan -v
mdadm: looking for devices for further assembly
mdadm: no recogniseable superblock on /dev/dm-1
mdadm: no recogniseable superblock on /dev/dm-0
mdadm: no recogniseable superblock on /dev/md2
mdadm: no recogniseable superblock on /dev/synoboot2
mdadm: Cannot assemble mbr metadata on /dev/synoboot1
mdadm: Cannot assemble mbr metadata on /dev/synoboot
mdadm: no recogniseable superblock on /dev/md1
mdadm: no recogniseable superblock on /dev/zram3
mdadm: no recogniseable superblock on /dev/zram2
mdadm: no recogniseable superblock on /dev/zram1
mdadm: no recogniseable superblock on /dev/zram0
mdadm: no recogniseable superblock on /dev/md0
mdadm: /dev/sdb5 is busy - skipping
mdadm: /dev/sdb2 is busy - skipping
mdadm: /dev/sdb1 is busy - skipping
mdadm: Cannot assemble mbr metadata on /dev/sdb
mdadm: /dev/sda5 is busy - skipping
mdadm: /dev/sda2 is busy - skipping
mdadm: /dev/sda1 is busy - skipping
mdadm: Cannot assemble mbr metadata on /dev/sda
mdadm: no recogniseable superblock on /dev/ram15
mdadm: no recogniseable superblock on /dev/ram14
mdadm: no recogniseable superblock on /dev/ram13
mdadm: no recogniseable superblock on /dev/ram12
mdadm: no recogniseable superblock on /dev/ram11
mdadm: no recogniseable superblock on /dev/ram10
mdadm: no recogniseable superblock on /dev/ram9
mdadm: no recogniseable superblock on /dev/ram8
mdadm: no recogniseable superblock on /dev/ram7
mdadm: no recogniseable superblock on /dev/ram6
mdadm: no recogniseable superblock on /dev/ram5
mdadm: no recogniseable superblock on /dev/ram4
mdadm: no recogniseable superblock on /dev/ram3
mdadm: no recogniseable superblock on /dev/ram2
mdadm: no recogniseable superblock on /dev/ram1
mdadm: no recogniseable superblock on /dev/ram0
mdadm: No arrays found in config file or automatically
猫/etc/fstab
none /proc proc defaults 0 0
/dev/root / ext4 defaults 1 1
/dev/mapper/cachedev_0 /volume1 btrfs auto_reclaim_space,ssd,synoacl,relatime,ro,nodev 0 0
猫/proc/mdstat
Personalities : [raid1]
md2 : active raid1 sdb5[3] sda5[2]
3902187264 blocks super 1.2 [2/2] [UU]
md1 : active raid1 sda2[0] sdb2[1]
2097088 blocks [2/2] [UU]
md0 : active raid1 sda1[0] sdb1[1]
2490176 blocks [2/2] [UU]
unused devices: <none>
编辑2：
光伏显示器
--- Physical volume ---
PV Name /dev/md2
VG Name vg1000
PV Size 3.63 TiB / not usable 1.75 MiB
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 952682
Free PE 0
Allocated PE 952682
PV UUID Yj7BOC-Ni0B-Q1NG-CHKy-Fmq0-620T-aHeUYR
显示
--- Volume group ---
VG Name vg1000
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 2
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 1
Open LV 1
Max PV 0
Cur PV 1
Act PV 1
VG Size 3.63 TiB
PE Size 4.00 MiB
Total PE 952682
Alloc PE / Size 952682 / 3.63 TiB
Free PE / Size 0 / 0
VG UUID grXROS-RIVn-C0Nx-cKqF-lOyB-YFHJ-HDWngh
lv显示器
--- Logical volume ---
LV Path /dev/vg1000/lv
LV Name lv
VG Name vg1000
LV UUID xgX5UJ-vk3r-eGX0-3bxj-339u-B3sV-y1jldv
LV Write Access read/write
LV Creation host, time ,
LV Status available
# open 1
LV Size 3.63 TiB
Current LE 952682
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 384
Block device 252:0
支持人员一开始就告诉我：
系统安装在 RAID md0 中，RAID 级别 1，通过后来添加的磁盘进行扩展（在故障安全方面，而不是增加）。交换位于 md1 上，也是 RAID 1。从 md2 开始，放置卷。NAS 的 RAID 配置没有问题，但卷 1 上的文件系统有问题。文件系统无法再安装。甚至连只读的都无法安装
编辑3： btrfs-显示-super /dev/mapper/cachedev_0
superblock: bytenr=65536, device=/dev/mapper/cachedev_0
---------------------------------------------------------
csum 0x63aa7385 [match]
bytenr 65536
flags 0x1
( WRITTEN )
magic _BHRfS_M [match]
fsid 1e556138-5480-44ce-8c65-bfa2d7fd54cb
label 2018.09.26-18:00:59 v23739
generation 3652464
root 547766255616
sys_array_size 258
chunk_root_generation 3579752
root_level 1
chunk_root 3611627094016
chunk_root_level 1
log_root 547767943168
log_root_transid 0
log_root_level 0
log tree reserve bg 0
total_bytes 3995837923328
bytes_used 2851638943744
sectorsize 4096
nodesize 16384
leafsize 16384
stripesize 4096
root_dir 6
num_devices 1
compat_flags 0x8000000000000000
compat_ro_flags 0x3
( FREE_SPACE_TREE |
FREE_SPACE_TREE_VALID )
incompat_flags 0x16b
( MIXED_BACKREF |
DEFAULT_SUBVOL |
COMPRESS_LZO |
BIG_METADATA |
EXTENDED_IREF |
SKINNY_METADATA )
csum_type 0
csum_size 4
cache_generation 18446744073709551615
uuid_tree_generation 3652464
dev_item.uuid 521f7cdc-497c-4c69-886e-c3974042337a
dev_item.fsid 1e556138-5480-44ce-8c65-bfa2d7fd54cb [match]
dev_item.type 0
dev_item.total_bytes 3995837923328
dev_item.bytes_used 3139713368064
dev_item.io_align 4096
dev_item.io_width 4096
dev_item.sector_size 4096
dev_item.devid 1
dev_item.dev_group 0
dev_item.seek_speed 0
dev_item.bandwidth 0
dev_item.generation 0
编辑4：
e2fsck -nvf -C 0 /dev/md2
e2fsck 1.44.1 (24-Mar-2018)
Warning! /dev/md2 is in use.
ext2fs_open2: Bad magic number in super-block
e2fsck: Superblock invalid, trying backup blocks...
openfs: invalid superblock checksum.
e2fsck: Bad magic number in super-block while trying to open /dev/md2
The superblock could not be read or does not describe a valid ext2/ext3/ext4
filesystem. If the device is valid and it really contains an ext2/ext3/ext4
filesystem (and not swap or ufs or something else), then the superblock
is corrupt, and you might try running e2fsck with an alternate superblock:
e2fsck -b 8193 <device>
or
e2fsck -b 32768 <device>
/dev/md2 contains a LVM2_member file system
e2fsck -b 8193 /dev/md2
e2fsck 1.44.1 (24-Mar-2018)
/dev/md2 is in use.
e2fsck: Cannot continue, aborting.
我如何安全地卸载、尝试命令并重新安装？
多谢！
答案1
您是否尝试过直接组装阵列？我的系统在重启时总会丢失阵列。我尝试过制作 mdadm.conf，但没有成功，因此我只能在下次重启时使用 create 命令重新组装它。只要设备的顺序相同，它就能组装得很好。就我而言，我使用 raid5：
mdadm --create /dev/md0 --level=5 --raid-devices=4 /dev/sd[a1,b1,c1,d1]
答案2
您的 RAID 没问题。MD RAID 超级块中的元数据是一致的。因此，我同意 Synology 支持，认为 RAID 完好无损。您可能仍想检查其数据，但我建议您等到数据恢复。
因此不要对其执行任何其他操作/dev/md2，也不要搜索任何内容，因为系统已经发现并识别了那里的内容。
系统发现它正在使用中，并阻止对它的访问，因为它知道它是活动卷组 (VG) 的物理卷 (LVM PV)，称为vg1000。在此卷组中，您有一个逻辑卷 (LV)，简称为lv。它是块设备，可以作为 访问/dev/vg1000/lv（它是指向某些 的符号链接/dev/dm-X，其中 X 是动态的，可以在重新启动或添加或删除另一个设备映射器实体后更改）。
接下来缓存层。我不知道它使用哪种缓存技术，但缓存卷在 /dev/mapper 内有名称，这使用 Linux Device Mapper 框架。其中一种技术是 LVM Cache。LV/dev/vg1000/lv是后备设备. 也可能有一个缓存设备。即使您目前没有安装任何 SSD，也可以创建此分层以方便进一步引入实际缓存。您可以将一些 SSD 放入其中，在 GUI 中勾选一些复选框，然后，您就会立即拥有一个缓存，而无需重新格式化和耗时的数据移动。
您的文件系统似乎位于此缓存卷中，它在系统中显示为/dev/mapper/cachedev_0（再次，它是指向某个块设备的符号链接/dev/dm-Y，其中 Y 是动态的）。文件中的以下行支持这一点fstab：
/dev/mapper/cachedev_0 /volume1 btrfs auto_reclaim_space,ssd,synoacl,relatime,ro,nodev 0 0
您应该在此设备上搜索 BTRFS 文件系统。尝试一下btrfs-show-super /dev/mapper/cachedev_0，它应该找到一个超级块。
您展示的屏幕截图提到了 上的问题/dev/dm-1。如果这是 的目标/dev/mapper/cachedev_0（请与 核实readlink /dev/mapper/cachedev_0），那么您就倒霉了。您可以尝试将此系统交给 BTRFS 专家，希望他能提取一些信息，但要准备好为此付费。