MAybe this is helpfull for others...
SItuation: MacMini, FMS11, Cisco switches (Gigabit), new gigabit house-installation. Then, a new Mini with FMS13, same db's, no network change at all in the period of switching the servers
REsult: After activating the new Mini (one of the latest sold items after the current Mini's were available), users were disconnected every second
OS were both non-server, the new Mini with Mavericks. Same ethernet-cable, the old Mini was removed from the network. We changed the ports on the switch without solving the issue. No sleep mode, etc. We called FM support, et all. No success
WE realized, that FMS did not 'cut' as long as we've been on the server using remote desktop (non of the Minis had monitors, all admin via remote desktop),
SO, we tried to ping the server machine - no connections were lost. When we stopped pinging, FM connections got lost every other second again. We 'solved' the situation by letting a client machine ping the server all around the clock...
WE set up the old Mini with FMS13 and installed that one with the db files, same result. That machine was running for a long time without any problems before - after installing FMS13, connections lost, every other second.
WE did some investigations, found out that there was a printer in the network that made problems as well (not availble for computers) and one of the sysadmins installed another switch (netgear, because no spare cisco was available at that time) -> printer was ok... I had situations with connection problems because of a power supply failure of a switch in the past - but that cisco switch was ok.
ANother sysadmin mentioned cisco to be 'more sensitive'...
I'm aware that FMS13 is slightly different when it comes to network traffic - but IMHO cisco's are expensive, but of good quality and technically OK.
ANyway, we asked for a replacement of the cisco switch (the one that served the rack, etc) - and a cheeper netgear switch was installed.
-> problem solved. No more lost connections...
THere might be other factors involved. So, the house installation is from a 'new' type, the wall connectors are multi-functional, etc. We thought that the problem with the printer could be based on that - but the Server was connected directly to the switch by ethernet cable.
BEsides of FMS13, every other network service was running without any problems (as was FMS11). I'm not a network guy, so I don't know any technical details of cisco's versus other brands. I don't know the exact type - but can ask for that if anybody is interested.
IF anybody knows of differencies between switches in this context, I would be happy to hear about!