Problem with external USB drive

[quarkslot]

I'm having problems with a new external HDD.

I already have 3 external HDDs (two USB and one FireWire) which I can mount using KDE Device Manager, no additional configuration was required to get them working.

I prepared the new drive exactly the same as my other USB drives by re-formatting it to EXT4 using KDE Partition Manager. After formatting Partition Manger shows type as "unknown" and won't allow me to assign a label to the drive, however from the command line the drive shows as EXT4.

I can mount the drive using device manager but there is no read/write access.

Any idea why this drive is behaving differently to my other USB HDDs?

The new drive is a Seagate, the others are Western Digital - though I can't think why this should make any difference.

Thanks

Nick

[Snowhog]

A Seagate drive, but what model? Is it a Passport? Seagate Passport drives have a special encryption designed for Windows users. There is a special encrypted partition that you have to get rid of first (IIRC). Normal formatting of such drives doesn't remove this partition.

[quarkslot]

Thanks - it's a Seagate Backup Plus.

http://www.seagate.com/gb/en/externa...kup-plus-desk/

I wondered if there might be a hidden/encrypted partition lurking somewhere.

I'll do some digging - if anyone has any pointers please let me know.

[Snowhog]

GParted LiveCD/USB should detect if such a partition exists.

[quarkslot]

Following your advice I went down the GParted LiveCD/USB route which identified 10MB of unallocated space - so I re-formatted the entire disk again as EXT4. This time the format took a while to complete - using KDE Partition Manager had been worryingly quick - and there was no space left unallocated.

Back in Kubuntu I was able to mount the drive but still denied read/write access, and KDE Partition Manager still cannot identify the filesystem of the disk drive.

I tried mounting the drive in Knoppix but this also refused to allow read/write access. The drive permissions showed Owner and Group as root whereas all my other external drives showed Owner as the currently logged in user i.e. knoppix.

For some reason when I mount the Seagate drive it retains root as the Owner instead of assigning the current user, I've no idea why this should be any different to the other external drives.

So I decided to create a new group called storage and assign this as the Owner of the drive, I added my user to the storage group and now when I attach the drive I have full access.

[Snowhog]

I've had such issues with my external USB HDs, where when connected (after having been formatted/partitioned) I didn't have read/write access. A 'quirk'? Not sure, but my solution was to write a small text file to the drive (as root), and then (as root) change the ownership of the file to myself (sudo chown paulaul * <<<< On the external HD). That gives me full read/write access to the entire drive.