Truenas Scale freezing with CMR Hot spares installed with SMR Pool

[Rendermandan]

All of my drives (10) in my pool are WD SMR 6TB Red drives. The pool is working fine. I know SMR are not the best for ZFS, but that is what I had before migrating to TrueNAS. and to be honest, I didn't' know there was a difference until joining this forum.

I wanted to add some hot spares so I ordered two 6TB WD Plus drives that are CMR.
The problem is with them installed as hot spares, Truenas keeps freezing shortly after installing them.

Is it possible they drive type is causing this? Mixing CMR and SMR drives.

 

[sretalla]

I wouldn't specifically agree that it's the mix that's a problem, but something about adjusting pool geometry may cause enough writes to all pool members (including or even mostly your SMR disks), which may cause a blocking condition in your pool, which if it's hosting your system dataset, will cause the system to lock up...

I would say what you're seeing is a result of widespread writes in a pool containing SMR disks and hosting your system dataset... check if that's true.

 

[Rendermandan]

I wouldn't specifically agree that it's the mix that's a problem, but something about adjusting pool geometry may cause enough writes to all pool members (including or even mostly your SMR disks), which may cause a blocking condition in your pool, which if it's hosting your system dataset, will cause the system to lock up...

I would say what you're seeing is a result of widespread writes in a pool containing SMR disks and hosting your system dataset... check if that's true.

I checked my System data set. It is set to the boot-pool. so I don't think that's it.

 

[Arwen]

Is your power supply powerful enough for 2 additional drives?

Just because the drives are installed, does not mean the power supply has enough power to allow the drives to seek and perform read / writes.

Please list all your hardware per forum rules...
And then list the output of zpool status for your data pool.