8TB USB External HD showing as 1.3TB max size

If your question pertains to using an external HDDs or even the USB Copy feature, post it here.
Forum rules
1) This is a user forum for Synology users to share experience/help out each other: if you need direct assistance from the Synology technical support team, please use the following form:

https://account.synology.com/support/su ... p?lang=enu



2) To avoid putting users' DiskStation at risk, please don't paste links to any patches provided by our Support team as we will systematically remove them. Our Support team will provide the correct patch for your DiskStation model.
bbos
I'm New!
I'm New!
Posts: 8
Joined: Thu Jan 21, 2016 10:52 am

8TB USB External HD showing as 1.3TB max size

Unread post by bbos » Sun Jul 15, 2018 7:41 am

I have a Synology 1515+ running the latest DSM (DSM 6.2-23739 Update 1). I have just put an 8GB External USB drive on it and reformated as EXT-4 but it is showing as 1.8TB max.

I have 3 such drives attached - The other 2 are 4TB and 2TB in size. They are showing as 1.7TB and 1.3TBs. Both in the External Devices control panel and in `df -h` from a shell.

Any idea why the full sizes are not being recognised?

User avatar
sciurius
Experienced
Experienced
Posts: 132
Joined: Thu Sep 05, 2013 9:35 am

Re: 8TB USB External HD showing as 1.3TB max size

Unread post by sciurius » Sun Jul 15, 2018 1:54 pm

What is the output of

fdisk -l /dev/XXXX

where /dev/XXXX is your external usb disk (commonly something like /dev/sdq).
DS418 / DSM 6.2-23739 Update 2 / 2 x WD40EFRX-68WT0N0 (SHR) / MailServer / MailStation / ownCloud / Transmission / ResilioSync / Syncthing / spotweb / LMS+Spotify
DS413 / DSM 6.2-23739 Update 2 / 2 x ST3000DM001-1CH166 (SHR) / Testing

bbos
I'm New!
I'm New!
Posts: 8
Joined: Thu Jan 21, 2016 10:52 am

Re: 8TB USB External HD showing as 1.3TB max size

Unread post by bbos » Mon Jul 16, 2018 12:24 pm

Code: Select all

/dev/sdr1          1.7T  1.7T  229M 100% /volumeUSB1/usbshare
/dev/sds1          1.3T   77M  1.3T   1% /volumeUSB2/usbshare
/dev/sdq1          1.8T  624G  1.2T  35% /volumeUSB3/usbshare

root@home-nas:~# fdisk -l /dev/sdr1
Disk /dev/sdr1: 1.7 TiB, 1801755678208 bytes, 3519054059 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

root@home-nas:~# fdisk -l /dev/sds1
Disk /dev/sds1: 1.3 TiB, 1404491104768 bytes, 2743146689 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

root@home-nas:~# fdisk -l /dev/sdq1
Disk /dev/sdq1: 1.8 TiB, 2000396190208 bytes, 3907023809 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

Squozen
Virtuoso
Virtuoso
Posts: 1341
Joined: Wed Jan 09, 2013 1:35 am

Re: 8TB USB External HD showing as 1.3TB max size

Unread post by Squozen » Mon Jul 16, 2018 2:40 pm

Just curious (I know this won't solve your problem), but if you connect it to your Windows machine and format it as an NTFS disk does the Synology see the proper size or is it still limited to 1.7TB?

peter247
Beginner
Beginner
Posts: 22
Joined: Thu Jun 14, 2018 6:58 pm

Re: 8TB USB External HD showing as 1.3TB max size

Unread post by peter247 » Mon Jul 16, 2018 5:50 pm

I was going to say the same , remove the partition and reformat with NTFS.
The only thing I can think of is the old problem with windows and maximum clusters which made a limit of 2TB.

User avatar
sciurius
Experienced
Experienced
Posts: 132
Joined: Thu Sep 05, 2013 9:35 am

Re: 8TB USB External HD showing as 1.3TB max size

Unread post by sciurius » Mon Jul 16, 2018 8:54 pm

please use fdisk -l /dev/sdq (etc) NOT /dev/sdq1 (no 1 at end)
DS418 / DSM 6.2-23739 Update 2 / 2 x WD40EFRX-68WT0N0 (SHR) / MailServer / MailStation / ownCloud / Transmission / ResilioSync / Syncthing / spotweb / LMS+Spotify
DS413 / DSM 6.2-23739 Update 2 / 2 x ST3000DM001-1CH166 (SHR) / Testing

bbos
I'm New!
I'm New!
Posts: 8
Joined: Thu Jan 21, 2016 10:52 am

Re: 8TB USB External HD showing as 1.3TB max size

Unread post by bbos » Tue Jul 17, 2018 11:26 am

Code: Select all

root@home-nas:~# fdisk -l /dev/sdq
Disk /dev/sdq: 1.8 TiB, 2000398934016 bytes, 3907029168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x230a2664

Device     Boot Start        End    Sectors  Size Id Type
/dev/sdq1         256 3907024064 3907023809  1.8T 83 Linux
root@home-nas:~# fdisk -l /dev/sdr
Disk /dev/sdr: 3.7 TiB, 4000787030016 bytes, 7814037168 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
Disklabel type: dos
Disk identifier: 0x1dbefbf6

Device     Boot Start        End    Sectors  Size Id Type
/dev/sdr1         256 3519054314 3519054059  1.7T 83 Linux
root@home-nas:~# fdisk -l /dev/sds
Disk /dev/sds: 1.3 TiB, 1404493455360 bytes, 2743151280 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0xf40e67de

Device     Boot Start        End    Sectors  Size Id Type
/dev/sds1         256 2743146944 2743146689  1.3T 83 Linux
root@home-nas:~#
I'll check one of the disks out on another machine.

bbos
I'm New!
I'm New!
Posts: 8
Joined: Thu Jan 21, 2016 10:52 am

Re: 8TB USB External HD showing as 1.3TB max size

Unread post by bbos » Wed Jul 18, 2018 1:49 am

I connected the 4TB and 8TB drives to my Mac.

I've had the 4TB for a while and it has backup data on it, however Mac's Disk Utility is telling me it contains a 1.4TB Linux partition and it has a 4TB capacity.

The 8TB has a 1.4TB linux partition and it has a 1.4TB Capacity. I tried to format it and no matter what format (Mac Extended, ExFat - I don't have FUSE setup to enable NTFS formatting), this figure doesn't change. I've contacted the retailer of it to ask it to be taken back and exchanged.

For the 4TB drive I'd like to start again. It currently contains Hyper Backup data on it - I'll need to copy it off first. Perhaps there was some bug in DSM at the time I formatted it.

Any other thoughts?

User avatar
sciurius
Experienced
Experienced
Posts: 132
Joined: Thu Sep 05, 2013 9:35 am

Re: 8TB USB External HD showing as 1.3TB max size

Unread post by sciurius » Wed Jul 18, 2018 4:19 pm

Is this external HDD in a package (i.e. fixed in a box with power supply and a USB cable)?
Or is it an external HDD in a USB adapter (a thing with power supply and USB cable where you can slide HDDs in)?

There are several USB adapters that do not support big (> 2GB, sometimes > 4GB) disks and show them as smaller disks to the system.
DS418 / DSM 6.2-23739 Update 2 / 2 x WD40EFRX-68WT0N0 (SHR) / MailServer / MailStation / ownCloud / Transmission / ResilioSync / Syncthing / spotweb / LMS+Spotify
DS413 / DSM 6.2-23739 Update 2 / 2 x ST3000DM001-1CH166 (SHR) / Testing

bbos
I'm New!
I'm New!
Posts: 8
Joined: Thu Jan 21, 2016 10:52 am

Re: 8TB USB External HD showing as 1.3TB max size

Unread post by bbos » Thu Jul 19, 2018 11:39 am

I have reformatted the 4TB drive and I have 4TB available. Great!

Ahh sciurius you've hit the nail on the head. I have been using an "external HDD in a USB adapter", however looking at the specs it only seems to support up to 2TB. And given the larger sectors on an 8TB drive I guess that is why I'm only seeing 1.4. I didn't realise there was a limit imposed by the adapter, though it makes sense that they can be bit limited (32 bits can only address 4TB).

Phew, that saved an embarrassing conversation with my suppliers when they send me a new 8TB drive and it also "fails". Looks like they'll make more money from me instead!

Post Reply

Return to “External Harddrives & USB Flash Drives”