Hi,

CONFIG_PARTITION_ADVANCED=y
CONFIG_MSDOS_PARTITION=y
CONFIG_EFI_PARTITION=y

That's all you need.

This could be the key. Sector sizes have been changing from 512 to 4096
over many years. If your kernel has been updated to expect/use 4096 byte
sectors, it might not be able to read the disk properly.

Sector size is only a (fixed) property of a specific block device, not 
something expected or required by the kernel.
Sector sizes other than 512B have been around for ages without any problems, 
even in consumer hardware (e.g. CDs and DVDs have 2KB sectors).

Disklabel type: dos

Device     Boot Start        End    Sectors   Size Id Type
/dev/sdb1           1 1953458175 1953458175 931.5G ee GPT

That looks... broken.
fdisk is recognizing the disk as MBR (a GPT disk would have "Disklabel type: 
gpt"), but the partition table is a protective MBR, which makes no sense in a 
non-GPT disk.

My guess is that this disk was at some time partitioned with GPT (possibly it 
came that way from WD?), but then it was only used in machines with no kernel 
support for GPT.
Such a machine will happily treat that as a normal MBR and allow you to access 
the protective entry as a normal partition, which means you can create a 
filesystem on it and fill it with data, destroying the GPT structures.

A GPT-aware kernel on the other hand will recognize that as a protective MBR 
and it will ignore it --but since the disk does not contain any valid GPT 
structures, it will not show any partitions.

Try running "gdisk -l /dev/sdb"; for a valid GPT disk it will say:

Partition table scan:
  MBR: protective
  BSD: not present
  APM: not present
  GPT: present

If that's not the case and you have no GPT, you will have to fix things 
manually.
Since the disk is only 1TB, there is no reason to use GPT at all, so your best 
bet is to use fdisk to make that a standard MBR by changing the partition type 
from 'ee' to '83'.

andrea

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