My network has a Windows Server 2003 file server, a handful of Macs running OS X 10.3.9 and two Macs running OS X 10.5.8. There are also a few Windows PCs that do not factor into this equation. The Windows Server 2003 server has both AFP and SMB shared volumes configured.
The two Macs running OS X 10.5.8 are experiencing a problem wherein they automatically close their AFP connection to the Server 2003 AFP shared volumes after about 20 to 40 minutes. Previously, when the AFP connections would drop, these Macs would automatically reconnect using SMB. This was an unacceptable situation as many Apple file capabilities required for our software (and available under AFP) are not available under SMB. I have since blocked all SMB traffic to the Macs in question (by modifying the ipfw configuration file to block port 139). Now, the connections to the AFP shared volumes simply close. If the user is working on a document, for example, that user must reconnect the shared volume before saving their work. The Macs running OS X 10.3.9 have no such unmounting problem, so this to me appears to be a Mac OS X 10.5 issue rather than a Server 2003 issue.
This seems to me to be a fairly straightforward situation, but I cannot find either a Mac or a Windows Server setting that would suggest automatically closing AFP connections to Mac OS X 10.5 only.
Thanks in advance for your help and I look forward to responses.