Time Machine corrupting hard drive partition

[Richard Harvey]

I have just acquired a new G Technology 1TB G Drive, using its Firewire 800 connection to my iMac Intel Core 2 Duo running OS 10.9.5. I have never used Time Machine previously, having always used SuperDuper. When I got this this new drive last week, I partitioned it w/2 partitions, dedicating one to Time Machine. I can mount and open that partition without a problem until I dedicate it to Time Machine and perform the first backup. After I dismount the drive and attempt to reboot it, I get the other partition just fine, but the TM dedicated partition either will not mount, or mounts but is corrupted and cannot be written to. Disk Utility says it needs repaired, but cannot repair it. I have erased the partition once, and rerun Time Machine, with the same results. I have erased and reformatted the entire drive (w/2 partitions) twice (once by doing a secure erase w/3 passes), and gotten the same results. I appears that it is Time Machine that is corrupting the partition.

 

[Spawn_Dooley]

How have you formatted the drive? Mac OS Extended (Journaled)?
If you leave the Time Machine drive connected, will it continue to perform routine back ups?

 

[Richard Harvey]

Yes, the drive is formatted Mac OS Extended (Journaled).
Actually, I did not leave the drive connected long enough to see if it would perform routine backups, though I assumed it would, since it perfumed the first back up. I do not normally leave my external drives connected to the computer, and I shut down my computer most nights, which means it would have to reboot the external drive when I turn on my computer anyway. The problem doesn't appear to be Time Machine's doing a back up, but in the fact that after the first backup the drive (at least when I reboot the drive) the TM partition becomes unwritable. When I reboot the drive I get a window alerting me that the partition cannot be written to. TM then alerts me that it can't do a backup to the drive. I also cannot eject the partition, and eventually it becomes also becomes impossible to eject the other partition. Soon the entire drive becomes unresponsive. The only way to recover is if I do at least a one pass erase from Disk Utility. A simple erase/reformat cannot be performed.

Now it turns out the situation is more complicated. I decided to abandon TM and only use SuperDuper. So I partitioned the drive afresh, and made a SuperDuper backup to one of the partitions. When I ejected the drive (both partitions) and then rebooted, I got the same results w/ SD that I've been getting w/ TM. I'll post a screenshot of the notice I get when I reboot the drive. I'm wondering if it's a hardware problem with the new drive, though it seems to work okay as long as I don't do a backup. I can simply copy files manually to the drive (partition) without doing a backup, and the drive will reboot just fine.

 

[Richard Harvey]

If I try to erase only the partition, this is what I get.

 

[honestone]

I would return the drive. Then, get a Seagate external device. Seagate drives work very well with Macs.

 

[Cory Cooper]

One more thing to check...

The drive may be formatted as Mac OS X (Journaled), but it may be partitioned as Master Boot Record instead of GUID. In Disk Utility, click on the orange icon line for the G-Tech HD - it should say something like 1 TB G-Technology - and look at Partition Map Scheme. It should say GUID Partition Table, not Master Boot Record. That will prevent the HD from being able to be repaired.

Of course, it could be a defective HD, but maybe not. That could also give Time Machine and/or SuperDuper! issues like you are experiencing. If it does show as Master Boot Record, you will need to partition it, not erase it, and use the Options... button to change it to GUID.

C

 

[Richard Harvey]

Thanks, Cory, for your suggestion. I was pretty sure I had made certain the Partition Map Scheme was set to GUID Partition Table, and when I double checked it was GUID. So that doesn't appear to be the problem. I'm giving up on the drive. Presently I'm doing a Secure Erase, then I plan to return the drive to Amazon for a refund or replacement. Wondering if I should simply have them send me a replacement G-Tech drive, or if I should switch to another brand like Seagate or LaCie.

 

[honestone]

I would return the drive, Richard, and get a Seagate one. Their reputation for working well with Macs is well established, and they are very dependable. In fact, the two external drives I have attached to my Mac Mini (also use them when backing up my MacBook Air) have Seagate mechanisms inside each one. They work flawlessly, including the SuperDuper! backups I make each week for both of my machines (to separate partitions on each drive, of course).

 

[Cory Cooper]

No worries...glad we checked.

I agree with you both...I would also return it, as it does sound defective.

I have had all the brands you listed - G-Tech, Seagate, and LaCie. They have all fared well over time, but I have had a couple fail. Even though HD technology has much improved over recent years, there are still failures out of the box. With HD failure, it's not a question of if, but when.

C

 

[honestone]

Yes, with hard drives, it is a case of when regarding failure. It has been my experience that if one keeps the drive as clean as possible, and performs disk maintenance/repairs on a regular basis (assuming of course no manufacturing defects), the drive will last between 5 and 7 years. That has been my exact experience with the Seagate drives that I have now/have owned in the past.

 

[Richard Harvey]

FYI, I returned the G-Tech drive to Amazon and ordered a LaCie drive. (I've had success in the past w/LaCie) Fired it up this morning, partitioned it, and have done both SuperDuper! and Time Machine backups to separate partitions. Both seem to be working fine. I've ejected and turned off the drive twice and rebooted. Everything appears to be in order. Apparently the problem was with the first disk.

 

[honestone]

Good to hear! Hopefully the LaCie drive will give you many, many hours of reliability!

 

[Cory Cooper]

Glad it's sorted and good luck with the new drive.

C