as long as the controllers aren't crap or RAID or something, this is irelevant. TrueNAS just needs direct access to the disks, how that happens it doesn't care, as long as it's reliable.
That's what I expected. The other 4 SATA ports are from a Marvell controller. I had a system with a Marvell Yukon network controller and it made me not want to get anything Marvell ever again! Seriously, that NIC would lock up so bad that power cycling wouldn't fix it. I had to make a DOS boot disk to run their diagnostics and that would fix it.
USB 3.0 sticks tend to just overheat and die anyway, and "speed" is irrelevant for the boot drive, not having it die is more important.
why rsync when you can replicate? unless the data changes really often, replication will be faster than rysnc. actually it will still probably be faster than rsync...
I am unfamiliar with this replicate feature. I will look into it. I have 2 basic external WD portable drives and I keep one home and one at a remote location. A few times a year I swap them. Regardless of how I sync the data, no USB3 connectors will significantly slow down the transfer. Yeah, it is not something I do often, but it is still annoying! :)
USB tends to be low power AND low reliability, all in one.... :\
My current NAS is a C2750-based Supermicro board booting off of 2 striped USB flash drives. Come to think of it, I'm not even sure if they are USB 2 or 3, but they have been working for about 6 years now.
I've also looked into the C3758D4I-4L and I like it better but you cannot find them anywhere. The 4-core version is on amazon but I would really prefer 8 cores.