I am using openshift for paas implementation. And, I am facing below error while trying to access the service which is in another namespace. "503 Service Unavailable, No server is available to handle this request"

Below is the sample setup I have tried: I have two namespace called defaultA and defaultB. In defaultA namespace, I have a service named serviceA,serviceAB and route named routeA and routeAB. In defaultB namespace, I have a service named serviceB and route named routeB .

ServiceAB in defaultA namespace is externalName type service which is mapped with serviceB (defaultB namespace) with below name serviceB.defaultB.svc.cluster.local

When I test routeB in my browser, I am getting expected web page. But, When I test routeAB which is also mapped with serviceB indirectly (through ServiceAB), I am getting ""503 Service Unavailable, No server is available to handle this request" error.

Please share your thoughts or ideas to fix this issue and please let me know if you need more information from my side.