i'm having a little trouble tracking down the cause of this one.
i have an ethernet SAN with Mac Pro server, 15TB CalDigit Storage, 6 port link agg connection to Edge Core switch serving 5 edit systems. when using Final Cut, at random times the edit system will start to beach ball, and then Finder will say that the SAN volume has become disconnected. the odd thing is that if you leave it alone for a few minutes and just close the disconnect window instead of clicking "disconnect" the computer will stay connected to the SAN volume and FCP will run fine. this seems to happen about every other day on different edit systems.
i have been using Final Cut when this happens, and i can't seem to figure out the cause. it just happens at random times. its not Final Cut related because it has happened to me when no applications were running. i thought at first it had to do with the edit systems falling asleep and maybe losing their connection that way. but i've had it happen while using Final Cut, so thats not it.
it doesnt seem like anything negative is happening on the server. its not losing connection with the storage. the bond is stable. all systems are at OS X 10.5.8. the Server is standard OS X and not OS X Server. Bob, i'm constantly thinking about the 10 client limit you found for regular OS X. could that be it? there are only 5 edit systems connected, but a number of laptops and iMacs could also be connected at any one time.
This is not a direct answer, but this is my observation.
First, when you get the disconnect, go to the server and go into Network>bond0 (your link agg port)>advanced, and make sure that the Small Tree card is showing "green lights" on all ports. If you see Red, you may have a defective card. I had this once, and it drove me crazy.
However, if you see all green lights (and your systems have the latest Small Tree driver on them for the Gig E card), but you still get a disconnect occationally, go to the server, System Preferences>Sharing and click off File Sharing, wait 10 seconds, and then click it back on. Can you reconnect now ? If you can't then reboot your server. Are you back on now ?
I realize this is intermittent, and this only happens once every 2-3 days, but it drives the client crazy - right ? I have a big client that this happens to randomly only about once a month, and it drives them crazy "I dont' care if it only happens once a month- why does it happen" - answer - Apple AFP sucks, and has issues - I have seen this on non video related Apple network forums discussing Apple AFP.
Of course (like many products) - some clients never see this problem, some see it once a month, and some, like yours see it every couple of days.
check the settings I just said in system preferences>Network, and make sure that your Small Tree card is ok, and that you have a current driver loaded into your server.
As for over 10 clients - I only have one client with more than 10 systems - they use NFS for everyone over client # 10- it works, and they have not called to complain. Of course, if you feel like loading in OS-X Server (which I never do), you can have unlimited AFP clients.