Is Yvon alive out there? Isn't this something useful enough that Thecus could kindly weigh in or lend a hand?
For those interested just in the possible answer, look at the last link.
I did some looking, and I found a number of sites that outline procedures using lvm2, which isn't compiled (as yet) for the n2100... In general, they were simply too complicated for me, or assumed a bootable raid or other complications that don't seem relevant.
A few of these are:
http://mkfblog.blogspot.com/2007/11/...partition.html
http://www.debian-administration.org/articles/424
This one seems to imply that mdadm --grow --size=max would actually do it all, but I think I must not be reading it correctly:
http://www.issociate.de/board/goto/1024674/
Finally, I found this site, which uses mdadm and resize2fs.
http://ubuntuforums.org/showthread.php?t=756407
I'm assuming I can ignore everything about creating boot drives and GRUB, and skip straight to the point at which both new drives are installed with healthy RAID1 at the original disk's partition size. Basically, I think I can start at the point "Expand the array to the new size"
It seems fairly straightforward. I'm hoping for some comment on it from people who know better, before I waste a lot of time trying to get it to work. Can it really be that simple?