UWL Task does not open over Internet - WebDispatcher as reverse web proxy

[Former Member]

Hello,

I have SAP NW 7.0 system with following Usage Types:

AS Java Application Server Java

EP Core Enterprise Portal Core Components

EP Enterprise Portal

XSS Self Services

BP ERP Business Packages (Portal Content)

Requirement was to make ESS available over Internet.

So I installed SAP WebDispatcher on DMZ host and configure it to forward incoming request using Public URL to the SAP NW system.

As ESS fetches data from back end system (ECC), SSO had to be configured between SAP NW and ECC system which also works fine.

Now Everything on ESS portal over Internet works absolutely fine apart from one particular WebDynpro link - UWL task which is opened in a new pop-up window but it makes call using internal SAP NW hostname and not Public URL.

As per my understanding and analysis, this is the problem as SAP WebDispatcher is not configured as full fledged reverse web proxy. But after going through all the available online resources I have come to the conclusion as WebDispatcher is bound to fail in such scenario and some third part reverse web proxy product is required. Somewhhere I also found that WebDispatcher with SPNego can be used as full fleded reverse web proxy but could not find anything further.

Please confirm my understanding/conclusion or suggest if still there is any workaround/solution to my problem.

Thanks & Regards,

Kashyap Shah

SAP Technology Consultant

[Former Member]

Just in case anyone encounters a similar problem, I've got the solution with a friend's help.

What happens in UWL task scenario is a call from Web browser made to the portal server with portal internal hostname which is maintained under WAS hostname Systems property of UWL system.

So the solution is to maintain the public URL/hostname under WAS hostname. Doing so will raise the question how would it be resolved while accessing the portal from company's private LAN then solution to that is make a DNS or hosts file entry of public URL/hostname against internal IP of portal server. As the order of lookup is in following sequence for hostname resolution: 1. Local hosts file under /etc 2. Local DNS assigned to the front-end 3. Public DNS

Now here one more thing to be taken care is that if there is a firewall between Internet and your company's internal network which is the usual case and you are forwarding incoming request on public URL/hostname on port 80 for e.g. to WebDispatcher which in turn forwards it to portal server on 5xx00 port then the WebDispatcher should be listening on port 80 only. So the entry under WAS hostname in Systems property is a public URL/hostname then without the port.

Please feel free to get back to me for any questions/queries as this is little complex, I know

Thanks & Regards,

Kashyap Shah

[Former Member]

Hello

I have a slightly different setup in that I am using a hardware load balaner (and HTTPS) instead of a Web Dispatcher. My goal is to have HTTPS terminate at the load balancer (via loadbalancer.domain.net) and then it will send to HTTP port of portal (portal.domain.net). As you experienced, all ESS functionality is working great, however the UWL inbox is coming back as HTTP. Oddly the hostname is correct - here is the full URL :

http://loadbalancer.domain.net/webdynpro/dispatcher/sap.com/tc_kmcbc.uwl.ui~wd_ui/UWL?sap-wd-cltwndid=WID1294498275837&sap-wd-secure-id=23db08651b4211e08b2400000015d2ea3430008903&sap-ext-sid=3qHPS71dY3w7hNY4X6Uw6Qk5PJv4eS4HT3G6YBWBg9Bw&sap-wd-norefresh=X&sap-ep-version=7.00.200912141055

I am not sure where you made the change regarding the WAS hostname --- in the UWL config there is a parmeter "Web Dynpro Launch System" - but it is currently set to portal.domain.net:50000 so I am not sure this would apply since that is not the URL coming back

I tried the URL generator service without success as described at this link - /message/8451415#8451415 [original link is broken]

Thanks for any advice!!

Edited by: Eric Poellinger on Jan 9, 2011 1:24 PM