I'd previously used aufs2 in aufs-tools with some luck, but apparently this package has been "superseded" (this is strange term to use for a package which seems to have been removed only because it no longer compiles, but never mind).
Okay, so I thought I would try to use unionfs-fuse. I can't for the life of me figure out how to make it work for users though.
I'm using this command to make my unified mount:
unionfs-fuse /mnt/disk1-pool=RW:/mnt/disk3-pool=RW /mnt/union-pool
When I run this as root, I cannot access this share as joe user:
$ ls -al /mnt ls: cannot access /mnt/union-pool: Permission denied ... d?????????? ? ? ? ? ? union-pool
When I run it as joe user, I cannot access this share as root. I basically get the exact same output as above. This is a little weird to me, root being root.
Both root (obviously) and joe user can access the /mnt/disk1-pool and /mnt/disk3-pool mounts.
If anybody has any info about aufs-tools for natty I'd also be interested. I am quite fond of this package because it worked.