How to debug an IIS 7 module? - iis

We had an IIS 7 module that was failing in a rather odd way (to us, at least) - the 32 bit version of the module apparently had some strange behavior where it would look for the 64 bit version of the DLL and use that if it was on a 64 bit machine, rather than the 32 bit version, since we installed the 32 bit version on purpose.
Before we figured this out (read: finally guessed correctly), the behavior the module was exhibiting was "simply not working" - no error message, the module was not writing log files like it normally does (because it wasn't working at all), nothing in the Event Log, nothing in the IIS logs except for an acknowledgement that we had made a POST request to the page exhibiting the non-working behavior.
My question is: to prevent using as huge a chunk of time as we did on this, is there any log file or files where we could have seen that 'such and such a module has failed' or 'XYZ module threw a BadImageFormatException to have given us even a slight clue as to what was going on?
Thanks in advance

You could use Global.asax Application_Error to redirect with Server.Transfer to a custom technical error page which will show HttpServerUtility server error with GetLastError().

Related

isapi dll force download

I have a legacy ISAPI dll, that generally fulfills requests just fine, but occasionally I will get prompted to save the dll from my browser. This is a known issue, with some good workarounds. IIS 8.5 serving dll for download instead of executing Hitting download will give you a zero byte file.
I am actually interested in doing the opposite of the workaround. How can I force this (incorrect) behavior, ie, is it possible to trick the server to download the full ISAPI dll? If so, what settings should I change. I am running IIS 7.5.
[EDIT] For clarity, I am not trying to hack anything client side. I doubt that's possible, but if it is I would really like to know. I am trying to figure out if it is possible to get the server to give up the dll with just a plain old post/get request. This is how I got it to give me the dll the first time, luckily it was zero bytes.
Thank you

Uncaught (in promise): The message port closed before a response was received

So before the question I wanna point out that the only thing I could find on this issue was on this stackoverflow question. This issue suggest that this was an issue with wappalyzer, and it was fixed in version 4.0.1. however I am using wappalyzer version 5.1.4 and is up to date with this.
I am building a web-app based on the MEAN-stack, everything worked as intended for a long time, until this error kept poping up in my google-chrome console:
Everytime i would click in my app header, and use my front-end routing to load up different components / modules this error appears, however I dont see any issue with what the web-app presents to me (it's not like I am missing data)
More details on the error:
I have no idea whats going on, or where this issue comes from.
This was due to a failing plugin.
Disable all plugins, and enable them one at a time to find failing chrome extensions.
In this case it was the wappalyzer extension.

Multipart file upload issue

I have a Koa application that has a multipart/form-data file upload that has suddenly stopped working. I have spent over 8 hours now trying to isolate the issue. What I've tried/verified:
Not a Node 6 issue; same problem occurs with Node 4 (which was previously working).
Have ruled out version issues in packages.json; have tested against originally working versions of all relevant packages, and latest versions.
Issue exhibits in latest Chrome and latest Firefox.
Issue does NOT exhibit when POSTing directly from Postman with exact same headers as browser is sending (excepting Cookie and Referer, neither of which can be set in Postman).
Problem exhibits with Koa wrappers koa-better-body and koa-multer.
Problem exhibits when directly using busboy, formidable, and even multiparty.
Similar to problems people were reporitng on this multer issue; tried all suggestions (including the long shot of adding field parameters before file parameter) to no avail.
Have tried to recreate minimal test case to reproduce, but have been unable to.
Have tried whittling down my app line by line, examining Babel output against minimal test case until they are functionally identical, problem still persists in my app, but not in test case.
All tests running on the same server, with the same browsers.
When debugging, the cleanest view of the problem is with formidable, in incoming_form.js. A single data event occurs:
Then an abort event:
After that, the browser eventually times out. (The file is larger than the 15 bytes being received in the first data event.)
I had hoped for a quick fix by switching from formidabl to busboy, and now I am a real bind, because this problem needs to get fixed, and I am running out of ways to look at the problem. I've tried to slice it every way I can think of, debug it every way I can think of, and short of writing my own multipart parser (not a task I would relish), I'm fast running out of options.
Has anyone run across this? Do you have any ideas how I might proceed with debugging or producing a minimum test case?
It turns out the issue was with koa-proxy: it doesn't correctly forward multipart POST requests. I fixed it by switching to koa-proxy2, and I will look into contributing a fix to the koa-proxy project.

Exception thrown. For more detailed information, please consult error-log-0.xml in XPage

I am running Xpage Application on Domino Server 8.5.3 FP1 Windows 64bit.
We are sending the bills(documents) around 2500 users. during testing ,this application works fine without any error. When we rollout the bills to user. All users are trying to open the application.
It is throwing the following error. But Application still works. At some point of time, Application gets slow and http hang. I have do restart of HTTP. Then it works fine.
I am not able to find the cause whether any error in the code or because number of users are accessing the application increases.
06/04/2014 10:58:53 AM HTTP JVM: CLFAD0211E: Exception thrown.
For more detailed information, please consult error-log-0.xml located in D:/Lotus/Domino/data/domino/workspace/logs
And sometimes this is also throwing ,
HTTP JVM: CLFAD0141E: Error processing XPage request. For more detailed information,
please consult error-log-0.xml located in D:/IBM/Lotus/Domino/data/domino/workspace/logs
Please help on this query.
You should start with what Paul suggests. If you haven't already downloaded and installed LogReader (by Jakob Majkilde), then you should. It is a database on your server that will read the various error file types and show them for you in an easy way. You can find it here: http://www.openntf.org/internal/home.nsf/project.xsp?action=openDocument&name=XPages%20Log%20File%20Reader
From these log files you will then have to look at where the system complains about problems. Did you write the code in Java or Serverside Javascript (SSJS)? You have options to debug both of these (although I cannot remember if you can debug SSJS in version 8.5.3 - it may not be available until version 9.0). But you could always add a println in the code near where you think it breaks ;-)
/John
At some point of time, Application gets slow and http hang. I have do restart of HTTP. Then it works fine.
As mentioned by Paul + John, no one is going to be able to give you an exact answer from the posted message.
As you mention the application gets slows and hangs, I would also recommend watching the XPages Masterclass.
It is approx 4 hours of videos, and goes into detail on how to debug your application for performance issues using the XPages Toolbox.
Again this isn't an exact solution. You will need to use the XPages toolbox to drill down on your code/JVM to see where it is slowing down/hanging.
Posting the stacks from the error-log-0.xml log file might give some hints, but with performance/hangs it's rarely that simple to find.
Now Application is working without issue. I have just included exception handling in all ssjs.
Now it is not throwing error.
Thanks for all your help and time.

Custom error messages for standard errors in Cognos 8

Our Cognos 8 application has an error affecting many users:
http://img543.imageshack.us/img543/6849/aoeu.png
CM-REQ-4158
The search path ... is invalid.
We know how to fix this problem (it's a browser configuration issue) but the error message is not helpful. Also, users will get this issue if they upgrade IE.
SO
Is it possible for us to modify this error message so it is more useful?
I believe the only way you'll be able to hone in on those messages is to use the Language Development Kit (LDK).. I'm sure you can edit them by hand, but I don't think it's worth it.

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