[vidarh]

Always mix batches almost regardless of what you buy. HDDs can and do fail like that too. I learned that the almost-hard way back in the day of the IBM Death Star [1], where we had a RAID that started failing, one drive at a time, roughly a week apart. We had reasonably up to date backups, but couldn't afford to take everything offline, so we were biting nails for weeks of continous RAID rebuilds and reduced performance and thankfully everything stayed up and we didn't get any additional failures during any of the rebuilds.

[1] https://en.wikipedia.org/wiki/Deskstar

[leonroy]

Finding different batches can be difficult, especially if like most companies you buy your kit from one or two approved vendors.

You often hear the trope 'don't mix different disk brands in RAID' wondering if anyone knows if that's true?