My question is :
Is there some way, using netbios alias or some other alias mechanism, whereby I could make the filer appear in the second domain's Network Neighbourhood, so that the users in the second domain could access it directly through their own port on the network card, instead of having to go through the first one ?
Actually, the particular filer interface that a client would use to communicate with a filer is not something that is directly influenced by the domain that it or the filer have been configured into. Domains are things that sit at a much higher level of abstraction than ip subnets and cables and so forth. On reading your message, it looks like you have configured all the clients on one subnet to be in one domain, and all the clients on another to be in a second domain, so you have got a one-to-one relationship between "clients that are in a X domain" and "clients that are on a particular ip-subnet", but that need not necessarily be the case. You could easily have half the clients on each subnet in one domain, and the other half from each subnet in another domain, but clients from *both* domains on a single subnet will normally communicate with the filer through the filer interface that is attached to that subnet, irrespective of which of the two domains the filer has been put into.
Make sense?
Keith