Why Grub 2 (ls command) can NOT see my logical (Extended) partitions, only primary! Grub4dos (geometry command) can see all my partitions on 3TB WD30EZRX hard disk.

honestly I have no idea.

Why does a 3TB hdd not have a gpt partition table?

are you having problems booting the OS?

I have Bios system, NOT EFI. I cannot boot also with Windows Boot Manager if Windows is installed on logical partition (on primary boots fine). Live Linux see all partition and also Grub4dos (haven't test booting).

That is the same as me, I have used GPT for years
as far as I know windows works fine with GPT.
But I don't use windows,
ok, well if it doesn't work provide as much information as you can so we can troubleshoot it.

Windows requires boot files to be on a primary partition marked as active and you can then install the system on a logical partition. You would need a separate boot partition on a primary partiton in this case and this has historically been the case with all windows. The other option is what you report, install on a primary partition.

Which Linux system are you using and which release? Grub should show all partitions on the drive not just primary. It may not show gpt partitions if you are booting from a dos (MBR) system if you do not have the gpt module. Might be a good idea to post more detailed info as suggested above.

All partitions on a GPT drive are primary.

https://unix.stackexchange.com/quest...artition-table

https://superuser.com/questions/3371...ical-partition