2 external HDDs failing AFTER Big Sur upgrade?? or?

[jz0309]

2 WD easystore USB 3 hard drives:
8TB now almost exactly 4 years old, used for TM backup - never seen any issue/error messages
4TB ~ 3month younger than above, used it for iTunes and some duplicate files, other than accessing music/movies no other day-to-day files
About 6 weeks ago II erased the 8TB drive to have a “clean” TM backup in prep for Big Sur upgrade.
Upgrade to Big Sur went seamless.
TM backups continued, no error messages.
iTunes drive worked fine, I re-arranged one folders/files and everything was working as before.
I started to see some high CPU usage of Finder, did some troubleshooting with Apple and it boiled down to the 4TB drive failing First Aid. But as I kept checking both drives, the 8TB drive started to show First Aid failures too.
I went onto the WD website and downloaded their disk utility tool, it has 3 sets: SMART check (never fails), quick test (takes ~ 2 minutes and never fails) and full test (that one failed).
So for the last 2 weeks or so I’ve run multiple experiments, erased the disks, format with APFS, created partitions and such. Sometimes First Aid fails all test, sometimes it doesn’t. WD utility most of the time fails the full test, but sometimes doesn’t.
A couple days ago I formatted the 8TB drive with APFS and then ran a full TM backup (just under 3TB), worked fine, but then the next scheduled TM backup failed.
Same story for the 4TB drive.

When I reboot the computer and then run the WD full test, both drives PASS.
Obviously I do not trust these drives anymore and have already got a 4TB SSD to use for my iTunes files and backup.

I currently use CCC for my backup.
I would like to have a full TM backup onto an external HDD …

I will do 1 more test with both drives: erase the drives, format with APFS and then use CCC to copy all my files.

So, 2 external HDDs fail within a couple weeks? Could be, I cannot rule that out …
Is there anything in Big Sur that could cause bad initialization/formatting of HDD?
Is Big Sur more sensitive to “failing” drives than Mojave was?
Has anyone experienced something similar after going to Big Sur?
Any other thoughts/suggestions?

 

[Hombre53]

I'd do a TM backup and check the results (restore to a spare external drive). CCC has been problematic on BigSur. I used to be an avid CCC user for the past 10 years but issues with BigSur pushed me back to Time Machine. You could have two HD's going bad, but the odds of that happening to both at the same time is a little weird.

 

[jz0309]

I'd do a TM backup and check the results (restore to a spare external drive). CCC has been problematic on BigSur. I used to be an avid CCC user for the past 10 years but issues with BigSur pushed me back to Time Machine. You could have two HD's going bad, but the odds of that happening to both at the same time is a little weird.

Thanks, I’ll test some more with TM as you suggested.
As for CCC, I know that you are limited with bootable clone options in Big Sur but are you talking about other issues?

 

[Hombre53]

The limited bootable clone options with CCC, in regards to BigSur, and it doesn't look like it will get any better in the future. For now, TM is my backup software.

 

[jz0309]

had both drives unplugged from the iMac for a day, plugged in this morning and ran First Aid and the WD utility.
8 TB drive: First Aid pass disk, failed container and partition, WD tool pass SMART and quick test, fail full test
4 TB drive First Aid pass disk and container, failed partition, WD tool pass SMART and quick test, failed full test

Next I erased both drives and reformat with APFS.
Copy my photos (1 parent many subfolders) of ~ 690GB to each drive via Finder - no error on both drives
Ran First Aid and WD utility again
8 TB: First Aid pass disk and container, failed partition, WD tool pass SMART and quick test, failed full test
4TB: First Aid passes disk, container and partition, WD tool pass SMART and quick test, failed full test

I'm done testing, I'm just totally frazzled that 2 drives fail within a short time of each other AND the co-incidence with the Big Sur upgrade 😂

 

[Hombre53]

had both drives unplugged from the iMac for a day, plugged in this morning and ran First Aid and the WD utility.
8 TB drive: First Aid pass disk, failed container and partition, WD tool pass SMART and quick test, fail full test
4 TB drive First Aid pass disk and container, failed partition, WD tool pass SMART and quick test, failed full test

Next I erased both drives and reformat with APFS.
Copy my photos (1 parent many subfolders) of ~ 690GB to each drive via Finder - no error on both drives
Ran First Aid and WD utility again
8 TB: First Aid pass disk and container, failed partition, WD tool pass SMART and quick test, failed full test
4TB: First Aid passes disk, container and partition, WD tool pass SMART and quick test, failed full test

I'm done testing, I'm just totally frazzled that 2 drives fail within a short time of each other AND the co-incidence with the Big Sur upgrade 😂

To have both drives go south on you in the same time period is just unreal. I don't blame you for being frazzled, I'd be that way too. 😕