Gateway error -- Websphere application

[ashwini751]

Hi All,

Good Day!!!!

We are able to access cognos application from BI servers (Dispatcher URLS), where as application is not accessible from gateway URL's.

Getting below error.

"The IBM Cognos gateway is unable to connect to the IBM cognos BI server. The server may be unavailable or the gateway may not be correctly configured.."UNKNOWN"".

We are having two BI servers and two gateway servers. Set up was working fine till last Saturday, all of a sudden it is not accessible. We have regenerated cryptographic keys also. And as mentioned in one of the IBM tech note, issue may be due to firewall changes. But as per our understanding, there were no any firewall changes made.

Please help..