I have a web chaining rule, which is passing all proxy requests onto an upstream server. It uses Basic authentication to port 8080, which is then authenticated by the upstream server.
This works fine, until the connection has been idle for a while. In order to re-establish the path to the upstream server, the downstream proxy initially tries to use CIFS for authentication purposes (I presume). However, CIFS is blocked by a FW rule on the downstream proxy itself, so it is denied. This doesn't stop it from trying, though. It tries 3 times, once after 3 secs and again after 6 secs. Once it realises that it cannot communicate using CIFS, it then switches to HTTP on port 8080, which works fine. Communication then continues using HTTP until the path needs to be re-established, when the process begins again.
This latency of 9 secs is starting to generate some complaints. Is there any way of configuring ISA Server 2004, so that it does not even try to use CIFS to communicate to the upstream server? Ideally, it would be aware that it always communicates using HTTP over 8080, and so would always use that protocol first (and preferably no others).