I have a client who recently upgraded from a single-machine FMSA8 deployment to a dual-machine FMS9 deployment. We have spent nearly a month trying to get Custom Web Publishing up and running, but we keep receiving "Maximum number of web sessions exceeded (Error 956)" errors whenever we make a query.

I have restarted both servers and redeployed the WPE numerous times, but this has not solved the issue.

Many of the articles I have read on this subject state that this is a Firewall problem, but they never say what the problem is exactly. I have checked the ports on both machines as well as the firewall using the FileMaker Tech Info 6427 resource, but with no luck.

My client's IT personel have even spent a couple hours in a conference call with FileMaker Tech Support, but it does not appear that they were able to come up with a solution.

Has anyone any information on this issue? Anything at all will be appreciated. Thanks.

E.J. Sexton

Well the most immediate reaction is to check in the Console how many simultaneous sessions you have set to be allowed.

Steven

From my similar experience (on Mac OS X Server), I would say it could be a firewall problem but could equally be a DNS problem. To see if it is the firewall, either open all ports between the two machines, turn on logging on your firewall for both allowed and denied packets between the two servers, attempt to deploy the WPE and you will soon see on which ports connections are being attempted.

In my case, I found there was no problem at all with the firewall. It appears that (at least on the Mac Servers) a Fully Qualified Domain Name is required on BOTH machines for the WPE to work. The FM Web Publishing app simply refused to start until this was set up.

I have checked the maximum number of web sessions in the admin console and it was set to the default 100 sessions. I tried changing the number of sessions and restarting/redeploying, but it did not solve the problem.

I have forwarded PBainbridge's post on to my client's IT guys to see what they make of it.

You were correct, we had a DNS problem. The worker machine could resolve the master machine using its IP address, but it could not resolve the master machine using its domain name.

The IT personnel modified the DNS so that the worker machine would be able to reference the master machine by its domain name and the issue was resolved.

I'm not overly familiar with how networks work, so I apologize if my description is lacking.

Thank you for all your help.