Session invalidated by firewall timeout

Technote (troubleshooting)   Problem(Abstract) After starting WebSphere® Portal, you notice that if you wait over an hour before logging onto the portal server for the first time, you receive the following error: Server Error Access Manager WebSEAL could not complete your request due to an unexpected error. Diagnostic Information Method: GET URL: /wass/wps/myportal Error Code: 0x38cf04d3 Error Text: DPWWA1235E Could not read the response status line sent by a third-party server. Possible causes: non-spec HTTP headers, connection timeout, no data returned. This is not a problem with the WebSEAL server. Solution Provide your System Administrator with the above information to assist in troubleshooting the problem.     Resolving the problem This error is generated by Tivoli® Access Manger WebSEAL, which can be used as a proxy server with WebSphere Portal. If the session is idle and the firewall times the session out before WebSEAL, that would cause an invalid session until the connection is re-established. This situation had the following values: WebSEAL session timeout= 600 seconds. WebSphere Portal session timeout= 10 minutes. Firewall session timeout=3600 seconds. In this particular case, the idle timeout (1 hour) was longer than the firewall timeout and therefore the session was invalidated. In order to address this issue, the firewall timeout must be increased or disabled. For cases where we may have idle time extend from the end of the business day until the next morning, it is common to set the firewall timeout to a value such as 14 hours.     Historical Number PMR 38571 999 758