Speaking of backup drives re. iMac

DH’s Time Machine backup drive for his new iMac has failed.**Needs a new backup drive for TM. His hard drive is about 500GB, I"m thinking he needs at least 1 terrabyte for a TM Backup. Maybe a portable San Disk or… etc…anyone have recommendations. thx for any advice/guidance.

For my DW’s new iMac, I have a USB connected 2 Tb spinning hard drive I partitioned into two halves, one for the use of Time Machine, the other for a backup from Carbon Copy Cloner, but the TM one is maybe all that’s needed, but my DW is our CFO, so I wanted some extra backup protection… Used it on her earlier iMac, too, but then she was using a memory stick for our vital files, made me nervous, so I’d do copies onto my Mac from time to time… So we retired that memory stick with the old iMac…

That was last year, today, I think I’d look at a similar SSD type of backup unit, faster, no physical spinning drive…

Check the reviews, costs…


I gave up on Time Machine after two disk were damaged, one of them a LaCie 1 terabyte.

Running First Aid on “Container disk5”

Repairing storage system
Performing fsck_apfs -y -x /dev/disk4s2
error: container /dev/rdisk5 is mounted.
Storage system check exit code is 65.
Storage system verify or repair failed. : (-69716)

Operation failed…

I’m convinced that Time Machine had something to do with damaging the disks. There is nothing wrong with the disk itself, you have to erase it to fix it but I no longer trust Time Machine.

Now I’m back to using SuperDuper with Flash Drives.

The Captain

Glad you got away from spinners for backup. But with respect, I see putting all your backups on a single device as approaching penny wise and pound foolish. I have never experienced a software failure that rendered data useless. Corrupted files yes. Software failure nota. Drive failures I have experienced - both spinners are SSDs. If you want to double your backup options, great, but do it on multiple physical devices.

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Tuni the sizing rule says TM backup should be twice the size to the data – not twice the size of the drive.

Open Finder, click on Macintosh HD and enter Cmd-I. This will show how much of the drive has data. Unless Bernie’s situation is very uncommon, his actual data total will be signicantly smaller then the Cmd-I number.

Time Machine is very capable and when the drive gets “full” it actually culls the oldest data - starting with files deleted from the HDD first. Next it goes with the oldest (datewise) versions of files that have a more recent copy.

I use either Sandisk Extreme or WD MyPassport SSDs – which ever is on sale. I actually have two SSDs making TM backups plugged into my Mac. I tried to put a link in here, but for some reason TMF would not accept it.

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GWP - Our iMac backups are not only the TM/Backup drive, but also copied over to my Mac as well, and it has a multitude of backups, from TM to the other drives I pulled from the old Mac Pro, all in an OWC unit… No worries, many, many duplicates, and when we travel, yet another copy of vitals on a thumb drive as well that I can access either from the MBA or my iPhone… Some are up in cloud services as well… Never can have too many backups! A while back I ran Disk Utility’s First Aid on my Mac Mini’s TM Volume… It churned away for a couple days, verifying 96 backup files on that drive, All Tests Pass, or ATP… It’s an old spinner, survivor, but I can’t remember the last time I even used TM… But they are there, just in case…

We use TM for getting stuff on new Macs. My wife got a new M2 Mac Mini last summer. About 50 days in a board went bad. They swapped the main board and returned the machine. Since memory is soldered on the main board, we used TM to get back in business.