It's a 2 bay Synology NAS with 2 x 6TB WD Red Drives. Today (and yesterday) I am getting multiple emails about Drive 2.

It now says 'Failing'. Yesterday it said 'Warning' and I am sure it said 'Critical' earlier in the morning.

I will replace the drive but not until next week.

The disk space used in Drive 1 is 2.2TB. Mostly media.

Could I temporarily replace Drive 2 with a 3TB WD Red Drive? Could I leave it in permanently (as my storage needs are not likely to grow significantly in the short term)?

The 3TB Drives are 2016 vintage and the 6TB Drives are 2017 and 2021. The 2021 drive is from PB Tech but I don't think I could approach them to claim under the 3 year warranty as I don't know the serial number of the drive at time of purchase. I have a login for PB Tech, but the Web Order Details don't show a serial number.

Could I purchase a Seagate Ironwolf 6TB instead of a WD Red. Therefore, the drives have different disk drive manufacturers.

Edit> I started an extended SMART Test but the log simply says that it failed.