External drive losing its name

[marty39]

I have two Firewire drives connected to a mid-2010 Mac mini running El Capitan. The drives are used for backup. Both are partitioned and each drive has a partition used for cloning the startup drive. The cloning software is scheduled to use one drive on MWF and the other on TuThSa and to eject the partition after completion.

On one of these drives the partition I use for cloning keeps losing its name. As a consequence the scheduled operation on this drive always fails and I can only get the clone operation started manually.

Disk Utility shows the partition as Untitled. It can mount the partition, and then it shows the name I gave the partition. After a day or two it again shows the partition as Untitled.

The command "diskutil list" shows the partition with a blank name and identifier "disk5s5." I can mount the partition with the command "diskutil mount disk5s5" and then the partition is shown with its true name. This lasts only a day or two. Sometimes another partition on the same drive, disk5s2, also loses its name, but less frequently.

Why does the partition keep losing its name? Does it mean that the drive is failing and should be replaced?

 

[chscag]

Why does the partition keep losing its name? Does it mean that the drive is failing and should be replaced?

Maybe.

However, we recommend NOT to partition a drive used for backing up. As inexpensive as external drives are nowadays, you should consider dedicating the entire drive for your cloned backup. If you have other uses for an external hard drive such as for Time Machine, use a separate drive for that.

I know it may be difficult to find external hard drives nowadays that are firewire, but your Mini also has 4 USB 2.0 ports.

 

[marty39]

Maybe.

However, we recommend NOT to partition a drive used for backing up. As inexpensive as external drives are nowadays, you should consider dedicating the entire drive for your cloned backup. If you have other uses for an external hard drive such as for Time Machine, use a separate drive for that...

It's a 2TB drive and I'm cloning a 300GB startup drive, and I have file backups on another larger partition. I can't really dedicate the whole drive to a clone. But I have a couple of 500GB drives I could use. They're USB, not Firewire, but I think I could boot the mini from them. That should solve my immediate problem.

But, why do you recommend not to partition a drive used for backup? I have two partitioned drives, as I mentioned, and the other one isn't giving me any trouble. Maybe because this drive has three partitions and the other has only two?

 

[MacInWin]

In general, backups should go to dedicated drives. That general approach is so that if/when you need the drive, you can get to the backups with no issue, no confusion. Today drives are relatively inexpensive, so for your 300GB start up drive, assuming about 250GB is used, a 500GB backup drive will be plenty large enough. And if you have a couple, I would suggest one be a TM backup and the other a clone, using something like SuperDuper or Carbon Copy Cloner. That way, when/if the internal drive fails you can boot from the clone, keep going while you want for the replacement internal drive to arrive and be installed. Then you can either clone the external to the internal or use TM to restore to the internal and get back to "normal" operations.

Partitioning a drive just adds a level of complexity that can fail. Any error in the partition table can cause the entire drive to be unusable. One partition is a much simpler setup and much less likely to have partition table issues.

The super large drives these days sound good, but when you have to partition that brand new 8TB or 10TB drive, the complexity goes up and reliability goes down. I stick with drives not larger than about 4TB, and those are in raid arrays in my NAS. For general use, 1-2TB is all you need. I have a lot of them for redundancy. (I just counted twelve, not counting the NAS. Yes, I'm a drive fanantic.)