Does smartd/swapoff/etc prevent hotswapping?

[tyjgHoVeqqNeAJUr]

Hello,

I have 6 FreeNAS boxes using 24-drive supermicro chassises. Each system has an 11-drive pool. In addition, I have four "offline" 11-drive pools. I rotate these "offline" pools in and out of systems to perform backups. I do this without powering down the machines. Of course, I export (or "detach" using FreeNAS lingo) these offline/backup pools before I hot-remove them.

I saw something unusual recently: smartd complained about some drives I had removed. Apparently FreeNAS automatically adds drives to smart.conf (perhaps upon import?). Strange that I never noticed this before.

This got me wondering... does FreeNAS swapoff drives during export?

Besides smartd and swapoff, are there other gotchas to my setup?

Thank you,

Chris

 

[mjws00]

When you detach it handles swap for you. The smartd thing is one I haven't explored so not sure how intelligently it handles things. Auto smartd is reasonably new. Not strange you didn't notice. I knew it was there but missed this implication. Thus my luddite status on 9.2.1.9 ;)

 

[tyjgHoVeqqNeAJUr]

Thanks. Unfortunately Jordan Hubbard disagrees in this bug report: https://bugs.freenas.org/issues/10163

He says that hot-swapping is "pretty much" not supposed to be done. He implies that swapoff is not called... but I would like some clarification.

 

[mjws00]

Excellent find. He confirmed exactly what I said. There is no way to unschedule smart.

Swap off is called appropriately. As for pulling a pool... He suggested a second head instead. That will work for some, other cases will not find that optimal.

Hot swapping is broken. That does NOT imply there is no use for it for anyone, ever. It takes a few minor tweaks.