By the way, since my upgrade from omv3 to omv4, I didn't do a pool upgrade. If I look at my pool status, I see the following message:
Now where omv4 is stable, I want to upgrade my pool. I don’t think that I ever get back to omv3.
Are there any known issues with upgrading the pool? How long does the 'zpool upgrade' take (min, hours or days)?
It’s usually seconds. I’ve upgraded all of mine.
I think the concern is that if you upgrade: will you always be able to get those drives in a system of at least that version? Probably. There were no additional upgrade prompts on 0.7.9 for me, so it’s the previous version that prompted. I think we’re at the point now where we can get to 4.16 and 0.7.9 easily.