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Level 1

6 points

External 3TB disk only showing 2.2TB

I have a iMac (27-inch, Late 2009) running Yosemite 10.10.5 and have attached an external two-drive enclosure which is equipped with eSATA and USB 2 connections.

When I insert a 3TB Seagate Barracuda drive in it and connect via USB2, Disk Utility only reports a 2.2TB drive and no matter how I erase/partition it that is the maximum I can achieve.

If I ask for 'Get Info' on the drive from the Finder it reports 2.2TB Capacity but also shows that there is 867.8MB used which is the missing capacity.

Does anyone have a clue how I can use the full 3TB?

Many thanks.

PS I have two of the 3TB drives and both report the same issue.

Posted on Sep 3, 2015 5:26 AM

20 replies

k3comms Author

Level 1

6 points

Sep 3, 2015 8:27 AM in response to k3comms

Apologies, I replied with the wrong name!!

Lexiepex

Level 6

14,102 points

Sep 3, 2015 8:38 AM in response to k3comms

I understood already. The problem is that DiskUtility is trying to partition as a bootable disk: WITH an EFI partition and A RecoveryPartition.

Maybe it does not try that when you start with formatting with 2 partitions as Drew said.

Lex

k3comms Author

Level 1

6 points

Sep 3, 2015 8:48 AM in response to Lexiepex

However I set the partition option I'm unable to choose anything that adds up to more than 2.2TB.

If I manually enter 3TB for one partition or 2 x 1.5TB for two etc then when I apply the setting it reverts to a max of 2.2TB

Sep 3, 2015 8:54 AM in response to k3comms

I do not believe your problem involves Disk Utility. It is likely your drive enclosures hardware, which is unable to see a drive larger then 2.2 TB. This has been a known issue ever since 3 TB drives (and larger) have been available.

I have two older enclosures that I no longer use because they have the drive size limitation.

I would start looking for a new enclosure.

Tom

k3comms Author

Level 1

6 points

Sep 3, 2015 8:58 AM in response to Tom Nelson1

Aha, that would explain the problem maybe.

I'll take a look around and see what I can find.

I will though check the FW800 enclosure I have - it is an Iomega Optimax with two bays.

I'll post my findings here as soon as I have something working (or not!)

Many thanks to everyone for your help.

External 3TB disk only showing 2.2TB