are multiple FSIDs supported?

[Ben DJ <bendj095124367913213465@gmail.com>]

Hello,

I'm building an NFSv4 FileServer.  My goal is to service multiple
machines on a LAN, each with their own, isolated namespace (I'm not
sure that's the right terminology).

Reading the man page it seems that only ONE fsid=0 export is allowed
per server.  And that subdirectories of that root CAN be exported, but
always under the same/one root.

That doesn't seem like "good isolation" to me.

My goal would be to export, for example

 /nfs1 & it's subdirs ONLY to LAN box1
 /nfs2 & it's subdirs ONLY to LAN box2
 etc

I've seen some mentions & discussion online of multiple-fsid's, where
/nfs1 would be exported as a root under fsid=0, /nfs2 under fsid=1,
etc.

But this approach doesn't look like its currently supported or
recommended.  Even if it was I haven't found anything that says how a
nfsv4 client would ADDRESS the specific fsid's.  Something in the
mount's URI I guess.

I know I might still be stuck in NFSv3 thinking about this, and NFSv4
subdirs might be isolated "well enough".

BenDJ