can't access 3TB GPT drive as USB
 

I have a 3TB GPT drive with a lot of information on it that I'd like to make available to my laptop using USB. The laptop show that the drive is "attached", (dmesg | tail) but doesn't give me any mount points. The drive has 9 partitions, and partition number 9 is the one I want to access, but dmesg shows it simply as "sdb", and none of the partitions are listed. There is a /dev/sdb but how do I mount it?

I tried: # mount /dev/sdb -t ntfs-3g /mnt/sdb9
but got:
Error opening '/dev/sdb': No medium found
Failed to mount '/dev/sdb': No medium found# mount /dev/sdb -t ntfs-3g /mnt/sdb9
Error opening '/dev/sdb': No medium found
Failed to mount '/dev/sdb': No medium found

Does your Linux support GPT?

i would not expect this to work
first is there a folder in "/mnt" called sdb9 ?
also the usb drive will have partitions
/dev/sdb1 , sdb2 , sdb3 ,....

Many current Linux distributions make partitions on external drives available under the /media or /media/user directory. Have you checked that? If you don't have any mount point there, then obviously, as pointed out above, you need to create it.

Yes, my Desktop does. This drive has been in my desktop for quite awhile, and working just fine (as an internal drive), but it won't open in USB. I'm not sure if the Laptop supports GPT, but I think it should. Its UbuntuMATE 16.04. And I'm getting the same feedback on both my Desktop and laptop machines.
=\=\=\=\=

I guess I'm too accustomed to the idea that in the Ubuntu/Mint world, USB devices get a name or number from the operating system. But yes, I did give sdb9 a mount point in Media also. Maybe I need to give sdb1,2,3,4,5,6,7,8 a mount point too, even all I'm interested in is sdb9. I'll try that.
==\\=\===\=\
You are absolutely right. I copied the line from an answer to someone else who was having about the same problem on his Windows computer. I also tried it by modifying that line in different ways, such as leaving out the "-t ntfs-3g". It didn't work that way either. I suspect I need something else in the middle there. But since it is an ext3 or ext4 partition, and a linux OS, I can't imagine what it might be. I'll try -t ext4 .

Thanks to all of you. I'll try again with your suggestions in mind, and get back to you.

Let's see the output of The mount command requires the partition you wish to mount, not the entire device - try

so this was a internal drive on a LINUX OS

why is to formatted to Microsoft Windows NTFS ?

unless you ARE sharing that one partition with a dual boot windows install

and is ntfs-3g installed and fuse set up ( if using fuse)

udev and systemd should AUTO mount is in /run/media/YourUserName/???? ( made on mounting )
normally the usb drive will be mounted ( by root) and read only for non root users
unless there is a udev rule for the uuid or name of the device

check out this link:
https://linuxconfig.org/howto-mount-usb-drive-in-linux

No media found usually means the OS is configuring the USB converter, but the drive connection to it has failed. You might try a new cable or reseat the drive in the connector.

Make sure your external usb enclosure supports > 2gb disks also. Some have 2tb limits.

+1 on check that the usb connection device supports > 2TB disks. I have one that I know maxes at 2TB. And many of my SDHC card readers seem to cap at 16GB, one of which caps at 8GB. And only some of those are bootable.

Also check that the bios / uefi supports the option. Most of this stuff is NOT something they print on the box. But might be in the manual, or various forums / reviews about the product.

I'm learning from your suggestions, but still, not mounting that USB. Here's what I have, and what I've done.

The partition I am interested in accessing is the 9th partition on the drive. It is on a GPT drive (3TB), and the partition itself covers most of that space (more than 2.5TB). It is not NTFS, but ext4, and has been serving me well as an internal drive in My Desktop machine,Which is:

A HP Pavilion a6110a with 6GB memory, and two other drives. Mounted internally it shows as sdb1,2,3,4,5,6,7,8 and 9. It boots to Mint 17 from drive sda.

The USB adapter I'm using is a: Sabrent USB-DSC8 The description of it includes:
“Sabrent USB-DSC8: driverless....connects any 2.5" or 3.5" Serial ATA/SATA Hard Drive, solid state drive (SSD) or desktop 5.25" CD/DVD-R/RW externally...USB3” and that it is backward compatible with USB2 and USB1

I turned the machine off, disconnected the cables and connected the power supply, and data cable, but didn't plug the data cable into the USB2 (my desktop doesn't have USB3).

After booting up from sda (Mint 17), I first ran
dmesg | tail and then plugged in the data cable, and ran the same command again:

$ dmesg | tail
[ 297.742182] usb 1-8: New USB device strings: Mfr=4, Product=5, SerialNumber=6
[ 297.742189] usb 1-8: SerialNumber: 20150201
[ 297.743024] usb-storage 1-8:1.0: USB Mass Storage device detected
[ 297.743800] scsi7 : usb-storage 1-8:1.0
[ 298.744859] scsi scan: INQUIRY result too short (5), using 36
[ 298.744883] scsi 7:0:0:0: Direct-Access Generic ATA/ATAPI Device PQ: 0 ANSI: 0
[ 298.745614] sd 7:0:0:0: Attached scsi generic sg4 type 0
[ 298.747210] sd 7:0:0:0: [sdd] Attached SCSI removable disk
[ 459.600619] JFS: nTxBlock = 8192, nTxLock = 65536
[ 459.725203] SGI XFS with ACLs, security attributes, realtime, large block/inode numbers, no debug enabled

$ ls /dev shows an sdd, and the dmesg tail seems to be identifying that as “Attached SCSI removable disk
”, but doesn't give me any partition names. This is essentially the same result I was getting yesterday, except for the two last lines. Perhaps that phrase "no debug enabled" holds a clue, but I wouldn't know how to "enable" it.

$ blkid shows only the mounted partitions.
$ lsblk -f shows all of the partitions on sda, and sdb, and sd0 (my DVD\CD drive), but nothing about sdd

$ sudo mount /dev/sdd /media/sdd9
mount: no medium found on /dev/sdd
$ sudo mount /dev/sdb0 /media/sdb9
mount: special device /dev/sdb0 does not exist

Does any of that give any of you a clue?

$ cat /proc/partitions

If it's not listed there, you have hardware / driver limits or need to do extra special stuff. Like lvm2 (lvscan / pvscan / vgscan)?

The answer in this post is interesting: superuser.com/questions/308492/is-there-a-size-limit-on-external-usb-hard-drives

I took a look at the sabrent site, but didn't see anything about your Sabrent having a disk limit, but also didn't see anything about not having a disk capacity limit either.

then why are you trying to mount a ext4 partition as a MS windows ntfs partition ?

also you are using "sdb?"
that should be a dvd or sd card drive

this is a usb housing so "lsusb" should see the drive if pluged in

now i place a entry in "fstab" and use uuid to auto mount a WD "my book" 4 tb drive

you should see entries in "/dev/disk/???" for it

or

as above there is a hardware issue

although fdisk can not work with GPT it will see it
and lsusb should also

plug in the usb drive and as root run
a usb should be sdc? or sdg? or sdh?

and if it is sdb?
then all that should be needed is
the file type should be detected
if not " mount -t ext4 /dev/sdb9 /mnt/sdb9 "