Dumb question: FMS12 is not set to disconnect inactive users, right?
Not a dumb question, but correct NOT disconnect
It can only be changed behaviour on sleep...
I've seen this behavior, even on my little iMac, even when working inside the database at the time. No network involved.
What causes it ... well, that's another question.
Yes, we also have gotten intermittent communication errors on FMP 8.5 and also 11 running Server 8.5. We checked cables, our UPS boxes, wall power, hubs, computer configs, time of day, phase of the moon, etc., but could not find any correlation that might lead us to the cause for that problem.
Is the OS X firewall on? or some other background process like the Notification Center Alerts? How about downloading sw updates in the background - may be on by default in ML? Energy Saver sleep settings?
If you ping the server for 3 minutes or so, how much packet loss do you see? You could also run Activity Monitor to see if anything is hogging the cpu cycles.
John may have turned his back for a moment on the FMS,
There are so many possibilities its hard to say where to start.
1. Frayed, intermittent, or loose Ethernet cable
2. Auto-negotiating Ethernet board or router switching speeds, yes this can cause a loss of connection eps. if it happens often.
3. Any of the pieces of hardware between the Host and client computers, incl. the computers.
4. Router with a corrupted router table
5. Power fluctuations or Ground Fault. Had an old buildings power wires not properly grounded and we had no noise margin left on the signal.
6. Ground Fault on any of the connecting equipment. (Esp. the routers in that hidden closet IS won't let you into because thats where all the Ethernet wires are jumbled together).
7. For those on Wireless having a low signal strength, switching between base stations, switching base channels.
8. Water cooler on the same power outlet causing sudden power drops when its cooler kicked in. This actually happend to me.
Sorry, I can't say where to begin let alone what might be wrong.
I had this happen to a client using a wireless LAN. They complained " We know the network is OK becasue the warehouse are using it to stream music on the internet and that works fine!"
Did some unscientific testing..
Ran my laptop overnight via wi-fi and a remote connection, no issues even when it slept while I did
Came into work and iMac had disconnected.
Put the timers right down and it does look like there is some changed behaviour in the Sleep on ML from Lion
I just need to make sure it never actually goes to sleep.....