Cognos may require its services to be restarted. This is seldom done. Typically a restart will clear up some of the known errors, including a "Gateway Error" received by users. Below steps must be done with notification to entire programming team before these steps are followed. The reboot MUST be done in this order.
STEP 1: RDP into ''cognos-db' and reboot.
STEP 2: RDP into 'cognos-app2' and reboot (wait 5 minutes as cognos-app2 comes up slowly).
STEP 3: RDP into 'cognos-app1' and reboot