External usb 3tb hard drive - unallocated

[dors]

Hi guys,
i'm moving from my old centos 6.5 pc to a new centos 7 laptop. Im planning to use an external usb 3tb hard drive to move files. I installed the hard drive directly to the centos 6.7 9(not as usb) formatted it as mbr and ext4. It worked like a charm, but when I put it back as the usb and try it on the laptop gparted show it as unallocated.
I read i had to format it as gpt, so I did, but the same thing is happening. I formatted it on the laptop as gpt and the pc will read it, but the pc is damaged and will crash every 20 minutes.
I dont know to handle this, is the disk, the way is formatted, which one format it?
Its the first time im working with a 3tb external hard drive, I dont know if that's the problem.

What should I do?

Thanks a lot for your help.

[dors]

I forgot to put this;

fdisk -l -u /dev/sdb

Disk /dev/sdb: 3000.6 GB, 3000592982016 bytes, 732566646 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 label type: dos
Disk identifier: 0x00000000

Device Boot Start End Blocks Id System
/dev/sdb1 1 4294967295 17179869180 ee GPT

[TrevorH]

Disk label type: dos

It's > 2TB in size so it needs a GPT label. Start over in fdisk on el7, delete all existing partitions then use the 'g' command to create a new GPT label then create a new partition and write the changes. Use mkfs to make a filesystem on the newly defined partition then try writing your data to it.

[dors]

Thanks!

I did that, format it as GPT and NTFS (I need to share it with a windows laptop too). But when I connect it directly to the centos 6 pc is show as unallocated again.
Everytime I switch between usb or direct I get the unallocated message. I need to do so because if I try to copy the info via usb, the pc will crash after 20 minutes (the pc is broken).

What else should I do?

Thanks once again

[TrevorH]

What's the output from uname -a ?

[dors]

This is the one:

Linux localhost.localdomain 2.6.32-696.1.1.el6.i686 #1 SMP Tue Apr 11 16:37:48 UTC 2017 i686 i686 i386 GNU/Linux

[TrevorH]

No idea what's going on but I suspect that USB devices on el6 are limited to 2TB though I'm not sure about that.