Cannot delete and resize external disk partitions

[superhua]

Using a clone function on a dual bay hard drive docking station, I cloned a 1 TB drive onto a 4 TB drive with the following results:

/dev/disk3 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *4.0 TB     disk3
   1:                        EFI EFI                     209.7 MB   disk3s1
   2:                  Apple_HFS 1 TB iPhoto Library     999.9 GB   disk3s2

Because I'd like for the iPhoto Library to use the entire 4 TBs, I tried to delete the 3 TBs of Free Space:

However, this fails:

I've read some of the other posts with similar issues, but am not sure how to best proceed short of using erasing the drive and cloning via Carbon Copy Cloner.

Thank you for any input!

 

[Fishrrman]

I've got no idea as to how these "cloning" docks work in actual practice, particularly with drives formatted for the Mac OS.

HOWEVER...

If you want to "do it right", I'd suggest this:
1. Get CarbonCopyCloner or SuperDuper. Both are FREE to download and use for 30 days. SD will work forever without registering, but only in "full clone" mode (you have to register it to do incremental backups).

2. Prepare your target drive. If you're going to need just 1tb (out of 4) for a cloned backup, I would use disk utility to erase the drive to Mac OS extended with Journaling enabled. I'd then partition it into 2 pieces:
first partition - 1tb
second partition - 3 tb (whatever's left)

3. Then I'd use CCC or SD to clone from the source drive (1tb) to the first partition.

4. I'd use the other partition for other stuff. But remember -- if there's anything important on it, you have to back that partition up, too!