I’m unsure if this is possible, but can I move an internal drive that is part of a pool out of my system to an external mount that is connected though eSATA? Will Rockstor/btrfs still detect it as part of the existing pool or do I have to use it like a brand new drive?
Can’t say for sure for eSATA, but i did several things with my rig. For example i deleted rockstor from the ssd from which it starts and replaced it with a standard ubuntu 1604 Desktop. All btrfs disks and pools with data where still there and usable directly under ubuntu without doing anything!
I have 1 8TB SEAGATE single disk and a 3 x 2TB RAID1 Array from which 1 disk is a usb3 external disk and 1 of this 3 is connected to a old HighPoint-RAID Card. Moving the disks around on the internal or external ports didn’t do any harm. But, as always, if there is sensible data on your disks, have a backup before you move on.
So for me, btrfs seems pretty solid in finding and recollecting its disks/arrays and pools regardless how they are connected.
I also cannot speak for eSATA, but I have moved disks from a Sata connector on the motherboard, to a USB to sata adapter, and Rockstor / btrfs still found and used the disks.
And I dont think eSATA is as big a change as that, so I think the disk would still be part of the existing pool.