我正在努力恢复客户的服务器。显然，机器速度变慢了，当他们重新启动它时，它启动到 dracut，声称找不到磁盘的 UUID。
在现在丢失的 LVM 上运行的原始操作系统是 RHEL 7。我添加了一个 10Gb 驱动器，并将 CentOS 7 安装到新驱动器上，以便有一个实时系统可以进行故障排除。
“自然”没有备份......
#pvs -a
PV VG Fmt Attr PSize PFree
/dev/sda1 --- 0 0
/dev/sda2 --- 0 0
/dev/sdb1 --- 0 0
/dev/sdc1 --- 0 0
/dev/sdc2 --- 0 0
/dev/sdc3 --- 0 0
/dev/sdc 是新驱动器，我正在尝试恢复 sda2 和 sdb1。
# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
fd0 2:0 1 4K 0 disk
sda 8:0 0 500G 0 disk
├─sda1 8:1 0 500M 0 part
└─sda2 8:2 0 499.5G 0 part
sdb 8:16 0 2T 0 disk
└─sdb1 8:17 0 2T 0 part
sdc 8:32 0 10G 0 disk
├─sdc1 8:33 0 1G 0 part /boot
├─sdc2 8:34 0 1G 0 part [SWAP]
└─sdc3 8:35 0 8G 0 part /
sr0 11:0 1 1024M 0 rom
PVScan 没有显示任何内容
# pvscan
No matching physical volumes found
Fdisk 仍然报告 LVM 分区
# fdisk -l
Disk /dev/sda: 536.9 GB, 536870912000 bytes, 1048576000 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x000a2e76
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 1026047 512000 83 Linux
/dev/sda2 1026048 1048575999 523774976 8e Linux LVM
Disk /dev/sdc: 10.7 GB, 10737418240 bytes, 20971520 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x000ddc56
Device Boot Start End Blocks Id System
/dev/sdc1 * 2048 2099199 1048576 83 Linux
/dev/sdc2 2099200 4196351 1048576 82 Linux swap / Solaris
/dev/sdc3 4196352 20971519 8387584 83 Linux
Disk /dev/sdb: 2199.0 GB, 2199023255552 bytes, 4294967296 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0xde7fc33e
Device Boot Start End Blocks Id System
/dev/sdb1 2048 4294967294 2147482623+ 8e Linux LVM
真正让我担心的是，磁盘的开头似乎是空的：
# dd if=/dev/sdb1 bs=512 count=255 skip=1
255+0 records in
255+0 records out
130560 bytes (131 kB) copied, 0.00671742 s, 19.4 MB/s
** 编辑：无缓存更新 ** VGScan 输出：
#lvmcmdline.c:2829 Parsing: vgscan -vvvv
#lvmcmdline.c:1881 Recognised command vgscan_general (id 141 / enum 127).
#config/config.c:1480 devices/global_filter not found in config: defaulting to global_filter = [ "a|.*/|" ]
#libdm-config.c:1002 global/lvmetad_update_wait_time not found in config: defaulting to 10
#daemon-client.c:33 /run/lvm/lvmetad.socket: Opening daemon socket to lvmetad for protocol lvmetad version 1.
#daemon-client.c:52 Sending daemon lvmetad: hello
#cache/lvmetad.c:143 Successfully connected to lvmetad on fd 3.
#filters/filter-sysfs.c:327 Sysfs filter initialised.
#filters/filter-internal.c:77 Internal filter initialised.
#filters/filter-type.c:56 LVM type filter initialised.
#filters/filter-usable.c:183 Usable device filter initialised.
#filters/filter-mpath.c:291 mpath filter initialised.
#filters/filter-partitioned.c:69 Partitioned filter initialised.
#filters/filter-md.c:169 MD filter initialised.
#filters/filter-composite.c:109 Composite filter initialised.
#config/config.c:1480 devices/filter not found in config: defaulting to filter = [ "a|.*/|" ]
#filters/filter-regex.c:216 Regex filter initialised.
#filters/filter-usable.c:183 Usable device filter initialised.
#filters/filter-composite.c:109 Composite filter initialised.
#libdm-config.c:975 devices/cache not found in config: defaulting to /etc/lvm/cache/.cache
#filters/filter-persistent.c:415 Persistent filter initialised.
#filters/filter-composite.c:109 Composite filter initialised.
#libdm-config.c:1074 metadata/record_lvs_history not found in config: defaulting to 0
#lvmcmdline.c:2897 DEGRADED MODE. Incomplete RAID LVs will be processed.
#lvmcmdline.c:2903 Processing command: vgscan -vvvv
#lvmcmdline.c:2904 Command pid: 10060
#lvmcmdline.c:2905 System ID:
#lvmcmdline.c:2908 O_DIRECT will be used
#locking/locking.c:129 File-based locking selected.
#libdm-common.c:984 Preparing SELinux context for /run/lock/lvm to system_u:object_r:lvm_lock_t:s0.
#libdm-common.c:987 Resetting SELinux context to default value.
#misc/lvm-flock.c:202 Locking /run/lock/lvm/P_global WB
#libdm-common.c:984 Preparing SELinux context for /run/lock/lvm/P_global to system_u:object_r:lvm_lock_t:s0.
#misc/lvm-flock.c:100 _do_flock /run/lock/lvm/P_global:aux WB
#misc/lvm-flock.c:100 _do_flock /run/lock/lvm/P_global WB
#misc/lvm-flock.c:47 _undo_flock /run/lock/lvm/P_global:aux
#libdm-common.c:987 Resetting SELinux context to default value.
#cache/lvmcache.c:2539 Dropping VG info
#cache/lvmcache.c:755 lvmcache has no info for vgname "#orphans_lvm1" with VGID #orphans_lvm1.
#cache/lvmcache.c:755 lvmcache has no info for vgname "#orphans_lvm1".
#cache/lvmcache.c:2086 lvmcache: Initialised VG #orphans_lvm1.
#cache/lvmcache.c:755 lvmcache has no info for vgname "#orphans_pool" with VGID #orphans_pool.
#cache/lvmcache.c:755 lvmcache has no info for vgname "#orphans_pool".
#cache/lvmcache.c:2086 lvmcache: Initialised VG #orphans_pool.
#cache/lvmcache.c:755 lvmcache has no info for vgname "#orphans_lvm2" with VGID #orphans_lvm2.
#cache/lvmcache.c:755 lvmcache has no info for vgname "#orphans_lvm2".
#cache/lvmcache.c:2086 lvmcache: Initialised VG #orphans_lvm2.
#cache/lvmetad.c:256 Sending lvmetad get_global_info
#label/label.c:833 Finding devices to scan
#device/dev-cache.c:1212 Creating list of system devices.
#device/dev-cache.c:723 Found dev 11:0 /dev/sr0 - new.
#device/dev-cache.c:763 Found dev 11:0 /dev/cdrom - new alias.
#device/dev-cache.c:763 Found dev 11:0 /dev/disk/by-id/ata-VMware_Virtual_SATA_CDRW_Drive_00000000000000000001 - new alias.
#device/dev-cache.c:763 Found dev 11:0 /dev/disk/by-path/pci-0000:02:01.0-ata-1.0 - new alias.
#device/dev-cache.c:723 Found dev 8:0 /dev/sda - new.
#device/dev-cache.c:763 Found dev 8:0 /dev/disk/by-path/pci-0000:03:00.0-scsi-0:0:0:0 - new alias.
#device/dev-cache.c:723 Found dev 8:1 /dev/sda1 - new.
#device/dev-cache.c:763 Found dev 8:1 /dev/disk/by-path/pci-0000:03:00.0-scsi-0:0:0:0-part1 - new alias.
#device/dev-cache.c:763 Found dev 8:1 /dev/disk/by-uuid/530982ac-2bdd-4310-857b-ff132f4a4d41 - new alias.
#device/dev-cache.c:723 Found dev 8:2 /dev/sda2 - new.
#device/dev-cache.c:763 Found dev 8:2 /dev/disk/by-path/pci-0000:03:00.0-scsi-0:0:0:0-part2 - new alias.
#device/dev-cache.c:763 Found dev 8:2 /dev/disk/by-path/pci-0000:03:00.0-scsi-0:0:0:0-part2 - new alias.
#device/dev-cache.c:723 Found dev 8:16 /dev/sdb - new.
#device/dev-cache.c:763 Found dev 8:16 /dev/disk/by-path/pci-0000:03:00.0-scsi-0:0:1:0 - new alias.
#device/dev-cache.c:723 Found dev 8:17 /dev/sdb1 - new.
#device/dev-cache.c:763 Found dev 8:17 /dev/disk/by-path/pci-0000:03:00.0-scsi-0:0:1:0-part1 - new alias.
#device/dev-cache.c:723 Found dev 8:32 /dev/sdc - new.
#device/dev-cache.c:763 Found dev 8:32 /dev/disk/by-path/pci-0000:03:00.0-scsi-0:0:2:0 - new alias.
#device/dev-cache.c:723 Found dev 8:33 /dev/sdc1 - new.
#device/dev-cache.c:763 Found dev 8:33 /dev/disk/by-path/pci-0000:03:00.0-scsi-0:0:2:0-part1 - new alias.
#device/dev-cache.c:763 Found dev 8:33 /dev/disk/by-uuid/0a81d8a5-6edd-40fb-ae16-14684f045ef7 - new alias.
#device/dev-cache.c:723 Found dev 8:34 /dev/sdc2 - new.
#device/dev-cache.c:763 Found dev 8:34 /dev/disk/by-path/pci-0000:03:00.0-scsi-0:0:2:0-part2 - new alias.
#device/dev-cache.c:763 Found dev 8:34 /dev/disk/by-uuid/52eb5eff-aa0c-435e-809c-5fbda45c6403 - new alias.
#device/dev-cache.c:723 Found dev 8:35 /dev/sdc3 - new.
#device/dev-cache.c:763 Found dev 8:35 /dev/disk/by-path/pci-0000:03:00.0-scsi-0:0:2:0-part3 - new alias.
#device/dev-cache.c:763 Found dev 8:35 /dev/disk/by-uuid/0dba35bd-de0b-4e59-b579-f9d3b18024d4 - new alias.
#device/dev-cache.c:723 Found dev 2:0 /dev/fd0 - new.
#filters/filter-type.c:27 /dev/fd0: Skipping: Unrecognised LVM device type 2
#device/dev-io.c:609 Opened /dev/sda RO O_DIRECT
#device/dev-io.c:359 /dev/sda: size is 1048576000 sectors
#device/dev-io.c:658 Closed /dev/sda
#filters/filter-partitioned.c:30 filter partitioned deferred /dev/sda
#filters/filter-md.c:99 filter md deferred /dev/sda
#filters/filter-persistent.c:346 filter caching good /dev/sda
#filters/filter-type.c:27 /dev/cdrom: Skipping: Unrecognised LVM device type 11
#device/dev-io.c:609 Opened /dev/sda1 RO O_DIRECT
#device/dev-io.c:359 /dev/sda1: size is 1024000 sectors
#device/dev-io.c:658 Closed /dev/sda1
#filters/filter-mpath.c:196 /dev/sda1: Device is a partition, using primary device sda for mpath component detection
#filters/filter-partitioned.c:30 filter partitioned deferred /dev/sda1
#filters/filter-md.c:99 filter md deferred /dev/sda1
#filters/filter-persistent.c:346 filter caching good /dev/sda1
#device/dev-io.c:609 Opened /dev/sda2 RO O_DIRECT
#device/dev-io.c:359 /dev/sda2: size is 1047549952 sectors
#device/dev-io.c:658 Closed /dev/sda2
#filters/filter-mpath.c:196 /dev/sda2: Device is a partition, using primary device sda for mpath component detection
#filters/filter-partitioned.c:30 filter partitioned deferred /dev/sda2
#filters/filter-md.c:99 filter md deferred /dev/sda2
#filters/filter-persistent.c:346 filter caching good /dev/sda2
#device/dev-io.c:609 Opened /dev/sdb RO O_DIRECT
#device/dev-io.c:359 /dev/sdb: size is 4294967296 sectors
#device/dev-io.c:658 Closed /dev/sdb
#filters/filter-partitioned.c:30 filter partitioned deferred /dev/sdb
#filters/filter-md.c:99 filter md deferred /dev/sdb
#filters/filter-persistent.c:346 filter caching good /dev/sdb
#device/dev-io.c:609 Opened /dev/sdb1 RO O_DIRECT
#device/dev-io.c:359 /dev/sdb1: size is 4294965247 sectors
#device/dev-io.c:658 Closed /dev/sdb1
#filters/filter-mpath.c:196 /dev/sdb1: Device is a partition, using primary device sdb for mpath component detection
#filters/filter-partitioned.c:30 filter partitioned deferred /dev/sdb1
#filters/filter-md.c:99 filter md deferred /dev/sdb1
#filters/filter-persistent.c:346 filter caching good /dev/sdb1
#device/dev-io.c:609 Opened /dev/sdc RO O_DIRECT
#device/dev-io.c:359 /dev/sdc: size is 20971520 sectors
#device/dev-io.c:658 Closed /dev/sdc
#filters/filter-partitioned.c:30 filter partitioned deferred /dev/sdc
#filters/filter-md.c:99 filter md deferred /dev/sdc
#filters/filter-persistent.c:346 filter caching good /dev/sdc
#device/dev-io.c:609 Opened /dev/sdc1 RO O_DIRECT
#device/dev-io.c:359 /dev/sdc1: size is 2097152 sectors
#device/dev-io.c:658 Closed /dev/sdc1
#filters/filter-mpath.c:196 /dev/sdc1: Device is a partition, using primary device sdc for mpath component detection
#filters/filter-partitioned.c:30 filter partitioned deferred /dev/sdc1
#filters/filter-md.c:99 filter md deferred /dev/sdc1
#filters/filter-persistent.c:346 filter caching good /dev/sdc1
#device/dev-io.c:609 Opened /dev/sdc2 RO O_DIRECT
#device/dev-io.c:359 /dev/sdc2: size is 2097152 sectors
#device/dev-io.c:658 Closed /dev/sdc2
#filters/filter-mpath.c:196 /dev/sdc2: Device is a partition, using primary device sdc for mpath component detection
#filters/filter-partitioned.c:30 filter partitioned deferred /dev/sdc2
#filters/filter-md.c:99 filter md deferred /dev/sdc2
#filters/filter-persistent.c:346 filter caching good /dev/sdc2
#device/dev-io.c:609 Opened /dev/sdc3 RO O_DIRECT
#device/dev-io.c:359 /dev/sdc3: size is 16775168 sectors
#device/dev-io.c:658 Closed /dev/sdc3
#filters/filter-mpath.c:196 /dev/sdc3: Device is a partition, using primary device sdc for mpath component detection
#filters/filter-partitioned.c:30 filter partitioned deferred /dev/sdc3
#filters/filter-md.c:99 filter md deferred /dev/sdc3
#filters/filter-persistent.c:346 filter caching good /dev/sdc3
#label/label.c:869 Found 9 devices to scan
#label/label.c:628 Scanning 9 devices for VG info
#label/label.c:664 Scanning submitted 9 reads
#label/label.c:683 Processing data from device /dev/sda 8:0 fd 4 block 0x56207e2a8870
#label/label.c:407 /dev/sda: No lvm label detected
#label/label.c:412 <backtrace>
#label/label.c:683 Processing data from device /dev/sda1 8:1 fd 6 block 0x56207e2a88c0
#label/label.c:407 /dev/sda1: No lvm label detected
#label/label.c:412 <backtrace>
#label/label.c:683 Processing data from device /dev/sda2 8:2 fd 7 block 0x56207e2a8910
#label/label.c:407 /dev/sda2: No lvm label detected
#label/label.c:412 <backtrace>
#label/label.c:683 Processing data from device /dev/sdb 8:16 fd 8 block 0x56207e2a8960
#label/label.c:407 /dev/sdb: No lvm label detected
#label/label.c:412 <backtrace>
#label/label.c:683 Processing data from device /dev/sdb1 8:17 fd 9 block 0x56207e2a89b0
#label/label.c:407 /dev/sdb1: No lvm label detected
#label/label.c:412 <backtrace>
#label/label.c:683 Processing data from device /dev/sdc 8:32 fd 10 block 0x56207e2a8a00
#label/label.c:407 /dev/sdc: No lvm label detected
#label/label.c:412 <backtrace>
#label/label.c:683 Processing data from device /dev/sdc1 8:33 fd 11 block 0x56207e2a8a50
#label/label.c:407 /dev/sdc1: No lvm label detected
#label/label.c:412 <backtrace>
#label/label.c:683 Processing data from device /dev/sdc2 8:34 fd 12 block 0x56207e2a8aa0
#label/label.c:407 /dev/sdc2: No lvm label detected
#label/label.c:412 <backtrace>
#label/label.c:683 Processing data from device /dev/sdc3 8:35 fd 13 block 0x56207e2a8af0
#label/label.c:407 /dev/sdc3: No lvm label detected
#label/label.c:412 <backtrace>
#label/label.c:763 Scanned devices: read errors 0 process errors 0 failed 0
#cache/lvmetad.c:2374 Scanning all devices to update lvmetad.
#cache/lvmetad.c:558 Sending lvmetad token_update update in progress
#cache/lvmetad.c:2412 Telling lvmetad to clear its cache
#filters/filter-type.c:27 /dev/fd0: Skipping: Unrecognised LVM device type 2
#device/dev-io.c:336 /dev/sda: using cached size 1048576000 sectors
#filters/filter-partitioned.c:37 /dev/sda: Skipping: Partition table signature found
#filters/filter-type.c:27 /dev/cdrom: Skipping: Unrecognised LVM device type 11
#device/dev-io.c:336 /dev/sda1: using cached size 1024000 sectors
#filters/filter-mpath.c:196 /dev/sda1: Device is a partition, using primary device sda for mpath component detection
#device/dev-io.c:336 /dev/sda1: using cached size 1024000 sectors
#cache/lvmetad.c:2247 Scan metadata from dev /dev/sda1
#cache/lvmetad.c:2260 No PV info found on /dev/sda1 for PVID .
#cache/lvmetad.c:1746 Telling lvmetad to forget any PV on /dev/sda1
#cache/lvmetad.c:784 Request to drop PV /dev/sda1 in lvmetad did not find any matching object.
#device/dev-io.c:336 /dev/sda2: using cached size 1047549952 sectors
#filters/filter-mpath.c:196 /dev/sda2: Device is a partition, using primary device sda for mpath component detection
#device/dev-io.c:336 /dev/sda2: using cached size 1047549952 sectors
#cache/lvmetad.c:2247 Scan metadata from dev /dev/sda2
#cache/lvmetad.c:2260 No PV info found on /dev/sda2 for PVID .
#cache/lvmetad.c:1746 Telling lvmetad to forget any PV on /dev/sda2
#cache/lvmetad.c:784 Request to drop PV /dev/sda2 in lvmetad did not find any matching object.
#device/dev-io.c:336 /dev/sdb: using cached size 4294967296 sectors
#filters/filter-partitioned.c:37 /dev/sdb: Skipping: Partition table signature found
#device/dev-io.c:336 /dev/sdb1: using cached size 4294965247 sectors
#filters/filter-mpath.c:196 /dev/sdb1: Device is a partition, using primary device sdb for mpath component detection
#device/dev-io.c:336 /dev/sdb1: using cached size 4294965247 sectors
#cache/lvmetad.c:2247 Scan metadata from dev /dev/sdb1
#cache/lvmetad.c:2260 No PV info found on /dev/sdb1 for PVID .
#cache/lvmetad.c:1746 Telling lvmetad to forget any PV on /dev/sdb1
#cache/lvmetad.c:784 Request to drop PV /dev/sdb1 in lvmetad did not find any matching object.
#device/dev-io.c:336 /dev/sdc: using cached size 20971520 sectors
#filters/filter-partitioned.c:37 /dev/sdc: Skipping: Partition table signature found
#device/dev-io.c:336 /dev/sdc1: using cached size 2097152 sectors
#filters/filter-mpath.c:196 /dev/sdc1: Device is a partition, using primary device sdc for mpath component detection
#device/dev-io.c:336 /dev/sdc1: using cached size 2097152 sectors
#cache/lvmetad.c:2247 Scan metadata from dev /dev/sdc1
#cache/lvmetad.c:2260 No PV info found on /dev/sdc1 for PVID .
#cache/lvmetad.c:1746 Telling lvmetad to forget any PV on /dev/sdc1
#cache/lvmetad.c:784 Request to drop PV /dev/sdc1 in lvmetad did not find any matching object.
#device/dev-io.c:336 /dev/sdc2: using cached size 2097152 sectors
#filters/filter-mpath.c:196 /dev/sdc2: Device is a partition, using primary device sdc for mpath component detection
#device/dev-io.c:336 /dev/sdc2: using cached size 2097152 sectors
#cache/lvmetad.c:2247 Scan metadata from dev /dev/sdc2
#cache/lvmetad.c:2260 No PV info found on /dev/sdc2 for PVID .
#cache/lvmetad.c:1746 Telling lvmetad to forget any PV on /dev/sdc2
#cache/lvmetad.c:784 Request to drop PV /dev/sdc2 in lvmetad did not find any matching object.
#device/dev-io.c:336 /dev/sdc3: using cached size 16775168 sectors
#filters/filter-mpath.c:196 /dev/sdc3: Device is a partition, using primary device sdc for mpath component detection
#device/dev-io.c:336 /dev/sdc3: using cached size 16775168 sectors
#cache/lvmetad.c:2247 Scan metadata from dev /dev/sdc3
#cache/lvmetad.c:2260 No PV info found on /dev/sdc3 for PVID .
#cache/lvmetad.c:1746 Telling lvmetad to forget any PV on /dev/sdc3
#cache/lvmetad.c:784 Request to drop PV /dev/sdc3 in lvmetad did not find any matching object.
#cache/lvmetad.c:558 Sending lvmetad token_update filter:3239235440
#vgscan.c:118 Reading volume groups from cache.
#toollib.c:2246 Processing each VG
#toollib.c:2294 Obtaining the complete list of VGs to process
#cache/lvmetad.c:1447 Asking lvmetad for complete list of known VG ids/names
#toollib.c:2314 No volume groups found.
#misc/lvm-flock.c:70 Unlocking /run/lock/lvm/P_global
#misc/lvm-flock.c:47 _undo_flock /run/lock/lvm/P_global
#cache/lvmcache.c:2539 Dropping VG info
#cache/lvmcache.c:755 lvmcache has no info for vgname "#orphans_lvm1" with VGID #orphans_lvm1.
#cache/lvmcache.c:755 lvmcache has no info for vgname "#orphans_lvm1".
#cache/lvmcache.c:2086 lvmcache: Initialised VG #orphans_lvm1.
#cache/lvmcache.c:755 lvmcache has no info for vgname "#orphans_pool" with VGID #orphans_pool.
#cache/lvmcache.c:755 lvmcache has no info for vgname "#orphans_pool".
#cache/lvmcache.c:2086 lvmcache: Initialised VG #orphans_pool.
#cache/lvmcache.c:755 lvmcache has no info for vgname "#orphans_lvm2" with VGID #orphans_lvm2.
#cache/lvmcache.c:755 lvmcache has no info for vgname "#orphans_lvm2".
#cache/lvmcache.c:2086 lvmcache: Initialised VG #orphans_lvm2.
#lvmcmdline.c:3050 Completed: vgscan -vvvv
答案1
在这个阶段，我们怀疑这是存储团队运行的某个流程的副作用。他们运行了一个“将未链接的块清零”的流程。所以我们猜测该流程造成了一些破坏。