You didn’t mention the version of TrueNAS or if you use encryption. How are the disks are attached to these machines? It is best to post detailed information on your system(s) so we can catch anything before you attempt migration. Your smart array controller may be a problem. I don’t know what the setting options are on those.
AVOID USB
What’s all the noise about HBA’s, and why can’t I use a RAID controller?
