Hi all,
I’m currently running openhabian on a thumbdrive attached to a Pi 3B so I’ve already got USB boot working. I believe I have two options:
Which would be the least problematic?
I think both would yield a similar result.
Personally I would choose backup and restore with os install. This way the disk is fully expanded to the size of the ssd. Some time image restores won’t do this. That is the only reason.
Does the etcher version fill the entire disk? I was under the impression they’ll be the same size anyway because they use the same source
I am not sure exactly what etcher does. I know the openhabian installer expands the disk at least it prints expanding the disk.
Amanda backup I believe will expand to fit and possibly shrink. That is part of openhabian. I have never used it but others on the forum have.
I have done option 2 a coupple of times
I use Win32DiskImager, and it copy the size of you source to the destination. So if you use a 16GB SD card, the size on the SSD will be 16GB as well…
But if you know Linux, you can either expand this size afterwards, or create more partitions. I dont know Linux well enough to do this, so I just live with my SSD no beeing used fully 
I actually have a phobia of resizing partitions on Linux I believe under utilisation of the SSD is actually beneficial in wear and tear?
If you have another drive to use for the backup image (or a network share), you can use Clonezilla to do the image and restore. IIRC, it will let you expand the image. You can always use something like gParted later to expand it too.
Alternately, you can load a fresh OS onto the SSD, configure your system, and then just copy the openhab config files across.