我已经将 4 个外部驱动器通过 USB 连接到我的 Dell Precision 490 工作站。
它们位于 /etc/fstab 中，以 uuid 形式存在，并且格式化为 UUID。
UUID=04c37bff-b93e-440e-acd0-3d984ddb2ec3 /mnt/drive0 ext4 defaults,nobootwait 0 2
UUID=210765f4-30e5-4863-a40b-aa1fffefe5ca /mnt/drive1 ext4 defaults,nobootwait 0 2
UUID=b981c5e7-249e-4430-9887-96ca674e0733 /mnt/drive2 ext4 defaults,nobootwait 0 2
UUID=22c8a274-3cf9-403f-9558-feb531e407c7 /mnt/drive3 ext4 defaults,nobootwait 0 2
我把三个驱动器放进去，但只有一个自动安装（驱动器 3，驱动器 2 仍然外部连接）
$ mount | grep /dev/sd
/dev/sdc1 on /boot type ext2 (rw)
/dev/sdb1 on /mnt/drive3 type ext4 (rw)
/dev/sdf1 on /mnt/drive2 type ext4 (rw)
但它们都出现了：
$ sudo fdisk -l
WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted.
Disk /dev/sda: 120.0 GB, 120034123776 bytes
<snip>
Disk /dev/sdb: 5001.0 GB, 5000981078016 bytes
255 heads, 63 sectors/track, 608001 cylinders, total 9767541168 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 identifier: 0xdd494cbf
Device Boot Start End Blocks Id System
/dev/sdb1 1 4294967295 2147483647+ ee GPT
Partition 1 does not start on physical sector boundary.
Disk /dev/sdd: 5001.0 GB, 5000981078016 bytes
42 heads, 62 sectors/track, 3750975 cylinders, total 9767541168 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 identifier: 0xec15dda8
Device Boot Start End Blocks Id System
/dev/sdd1 256 1220942644 610471194+ 83 Linux
Disk /dev/sde: 5001.0 GB, 5000981078016 bytes
255 heads, 63 sectors/track, 608001 cylinders, total 9767541168 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 identifier: 0x4cd5215a
Device Boot Start End Blocks Id System
/dev/sde1 63 1220942644 610471291 83 Linux
Partition 1 does not start on physical sector boundary.
Disk /dev/sdc: 500.1 GB, 500107862016 bytes
<snip>
Disk /dev/sdf: 5001.0 GB, 5000981073920 bytes
255 heads, 63 sectors/track, 76000 cylinders, total 1220942645 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 identifier: 0x6b6805d9
Device Boot Start End Blocks Id System
/dev/sdf1 63 1220942644 588803032 83 Linux
$ ls /dev/sd*
/dev/sda /dev/sda1 /dev/sdb /dev/sdb1 /dev/sdc /dev/sdc1 /dev/sdc2 /dev/sdc5 /dev/sdd /dev/sdd1 /dev/sde /dev/sde1 /dev/sdf /dev/sdf1
如果我尝试正常挂载：
$ sudo mkdir /mnt/temp
$ sudo mount -t ext4 /dev/sde1 /mnt/temp
mount: wrong fs type, bad option, bad superblock on /dev/sde1,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so
$ dmesg | tail
[87143.301150] EXT4-fs (sde1): VFS: Can't find ext4 filesystem
[87295.537835] EXT4-fs (sde1): VFS: Can't find ext4 filesystem
[87315.780147] EXT4-fs (sde1): VFS: Can't find ext4 filesystem
[87315.780290] EXT4-fs (sde1): VFS: Can't find ext4 filesystem
[87315.780421] EXT4-fs (sde1): VFS: Can't find ext4 filesystem
该机器有 5 个 SATA 端口，我还买了一个 PCIe SATA 控制器并尝试了它。没有区别。在端口之间移动设备仍然没有区别。另外两个驱动器始终安装。
我将它们放回带有 USB 控制器的相应外部外壳中，它们就可以正常工作了。尽管当我尝试使用其中一个直接连接的驱动器的外壳时，它无法被识别。
谢谢！
编辑：添加来自 gdisk 的输出
$ sudo gdisk /dev/sde
GPT fdisk (gdisk) version 0.8.8
Partition table scan:
MBR: MBR only
BSD: not present
APM: not present
GPT: not present
***************************************************************
Found invalid GPT and valid MBR; converting MBR to GPT format
in memory. THIS OPERATION IS POTENTIALLY DESTRUCTIVE! Exit by
typing 'q' if you don't want to convert your MBR partitions
to GPT format!
***************************************************************
Command (? for help): p
Disk /dev/sde: 9767541168 sectors, 4.5 TiB
Logical sector size: 512 bytes
Disk identifier (GUID): 00C22148-8C82-4062-BEC5-6759E7E23856
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 9767541134
Partitions will be aligned on 8-sector boundaries
Total free space is 8546598519 sectors (4.0 TiB)
Number Start (sector) End (sector) Size Code Name
1 63 1220942644 582.2 GiB 8300 Linux filesystem
$ sudo gdisk /dev/sdb
GPT fdisk (gdisk) version 0.8.8
Partition table scan:
MBR: protective
BSD: not present
APM: not present
GPT: present
Found valid GPT with protective MBR; using GPT.
Command (? for help): p
Disk /dev/sdb: 9767541168 sectors, 4.5 TiB
Logical sector size: 512 bytes
Disk identifier (GUID): E76C335B-FBA1-4FE0-9DC2-C5CADBECA6B0
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 9767541133
Partitions will be aligned on 8-sector boundaries
Total free space is 0 sectors (0 bytes)
Number Start (sector) End (sector) Size Code Name
1 34 9767541133 4.5 TiB 8300 disk4
有趣的是，看起来未安装的磁盘使用 MBR 而不是 GPT？
答案1
这听起来像是https://superuser.com/questions/679725/how-to-correct-512-byte-sector-mbr-on-a-4096-byte-sector-disk：USB 外壳报告的扇区大小与主板不同，因此分区表的解释不同。
我曾遇到过类似的问题，当时我将一个 4TB 磁盘从 USB 外壳移到了内部 SATA 端口。显然，USB 外壳报告了 4k 扇区，因此我能够使用老式的 MBR 分区表来创建 4TB ext4 分区。通过 SATA 连接磁盘后，ext4 分区再也找不到了，显然是因为现在磁盘的访问扇区为 512B。
我通过以下步骤解决了这个问题，使用测试盘Ubuntu 中可用的数据恢复工具：
- 为安全起见，创建了原始分区表的备份（
sfdisk -d /dev/sdb > sfdisk-sdb.txt） - 用于
testdisk /dev/sdb查找原始 ext4 文件系统 - 让 testdisk 将新的 MBR 分区表写入磁盘
- 由于 MBR 表不支持 4TB 分区，因此 ext4 分区仍然无法挂载，并出现错误
EXT4-fs (sdb1): bad geometry: block count 976751744 exceeds size of device (536870911 blocks) - 用于
gdisk /dev/sdb将MBR转换为GPT格式，并将GPT写入磁盘 - 再次用于
testdisk /dev/sdb查找原始的 ext4 文件系统（它检测到了错误的文件系统类型，但这并不重要），并让它将新的 GPT 表写入磁盘 - 用于
gdisk /dev/sdb将错误检测的文件系统类型更改为8300
也许我只是运气好，但经过此过程后，ext4 文件系统可以照常挂载。fsck -f /dev/sdb1没有检测到任何错误，并且blkid /dev/sdb1给出tune2fs /dev/sdb1与使用 USB 外壳时相同的结果。