We have DataPower (7.2.0.x, virtual edition) at customers environment. A lot of different access cases are working fine. But there is one web enabled product in the backend called QlikView from qlik.com. The application works ok to log in, you can browse around but there are so called documents opened, and that does not work through DataPower (it works when accessed directly from intranet). We have traced and analysed various parts of the chain including QlikView on it's server. So far the two requests (intranet - success, internet through DataPower - fail) look exactly the same on server side, but DataPower request gets 'document not found'.

We have qlik.com representative involved and he mentioned that have heard similar problems and that they've been fixed by 'DataPower Proxy Settings'. I'm sure he will try to investigate what those settings were, but I'd like to reach out to you - if any of you have had this situation and could tell if this is related to http headers or something else that can be set on DataPower.

Hi Jarkko,

What kind of service are you using? Multiprotocol Gateway? Web Application Firewall?

We have Multiprotocol Gateway.

Hello,

We just had an issue with one back-end system with browser access, that was related to "Follow Redirects" -setting (under MPG > Advanced -tab, we had to disable it so that 302 response was passed to browser instead of DP trying to follow the redirect), but I assume you'd have noticed if it was this simple difference in the HTTP request flow in your case..

Br, Panu

This "Follow Redirects" is worth checking. But I'm not too optimistic on finding the cause from that type of thing. We traced the success and fail cases today in efforts of finding if some http header would be the culprit. There is a redirect involved, but the resulting POST request comes to backend server and as far as Qlik support was able to check that from server logs, both requests (success and failure) look the same.

Qlikview is using WebSockets and that might be the reason you are facing problems with  some of the flows. WebSockets is supported on DataPower. Check port 4244

Hi,

Can you please send error log message. So, that I can support on this problem. 

Thanks.

Asif

In Reply to Serge Vereecke:

Qlikview is using WebSockets and that might be the reason you are facing problems with  some of the flows. WebSockets is supported on DataPower. Check port 4244

We tried with this "Follow Redirects" setting. It was indeed enabled. But disabling it did not help. Customer, end-user who needs to do the tests, has been, extremely busy.

The problem is partly, that we don't have much errors anywhere (DP, IHS, QlikView Server). Just the QlikView answering for the "important" call with "not found".

Actually it turned out that this "Follow Redirects" setting exposed our backend hostname to client and thus does not work at all. We are back to square one.

We've been told that another customer with QlikView has solved similar problem with "DataPower proxy settings". As it is between that 3rd party's customer with IBM, we don't have details on that.

You need to re-enable that setting and define a response rule to correct the location header of the redirects.

Match on error code 302 and use the dp:set-response-header extension function to adapt the location header in a way that it does no longer point to your backend, but to the correct URL of your gateway.

Also try the option "Process Messages Whose Body Is Empty" in the advanced properties of the MPGW. This has nothing to do with redirects, but is needed for certain web applications.