Hey Arturo... yeah, unfortunately, I haven't had re-shares work well -- regardless of what server is actually doing the sharing (the backup would be a good choice if you really needed to do it, though).
The problem is that Xsan is (in my experience) not great at prioritizing file sharing workload over actual real-time video throughput. So, if you have a few clients connected over AFP/NFS/Whatever all trying to copy files to and from the SAN, but you also have edit suites working with fibre channel in real time, you might get dropped frames and overall bad performance.
Xsan simply sees all requests for files as equally important, and even though YOU don't really care if a file copy over AFP takes a few extra seconds -- when compared to a real-time request to an edit suite over fibre channel that you want to be taken care of RIGHT AWAY -- Xsan won't prioritize the fibre channel traffic over file sharing. Also, Xsan used to be really bad with essentially giving AFP clients pretty much full bandwidth all the time -- if a file sharing client was connected over AFP, it just sucked as much bandwidth as possible, even when it wasn't DOING anything.
What I do is create a "Bridge" volume that people use to copy files to and from the Xsan. Another option is Final Cut Server. This is a longer description from a couple months ago:
http://forums.creativecow.net/readpost/180/856757
Now, I haven't tried AFP reshares much in Xsan 2, so it's possible it works better now. But, I'm still skeptical that a single system can serve file-sharing needs to lots of clients and still be an effective SAN providing real-time response to edit suites. If you or someone has made it work well, I'd love to hear about it.
One suggestion that Matt Geller had in his book about Final Cut Server could apply to general file sharing if you needed to reshare an Xsan. He said that you should setup a dedicated server to host Final Cut Server, and when you connect that server to your Xsan, you could unplug one of the fibre channel cables (so only a single fibre channel cable connected Final Cut Server to the Xsan). This moderates the bandwidth that Final Cut Server uses down to whatever a single cable can provide. You could try applying this idea to an Xsan reshare; setup a dedicated server to take care of the AFP/NFS reshare of your Xsan, and only connect it to your fibre channel switch with a single cable. I haven't done it and don't recommend it, but if you really need a reshare, it's worth a shot.
Hope that helps -- the Xsan reshare is a complicated issue, and I know I thought it would work when I started out a few years ago. It just hasn't made me happy. Let me know if you have questions, and have fun!
