Last post Jun 19, 2020 04:57 PM by PatriceSc
Jun 11, 2020 06:14 AM|larka74|LINK
I have developed a service that handles incoming orders, one at a time everythings works fine.
But when there is two calls at the same time, the second call gets a response "500" as an internal server error.
I do NOT see anything from my service, nothing in my logs, my application is not started at the webserver with data from call #2.
Checking normal IIS logs I dont see any timeouts or errors. Empty.
When I check the "Failed Request Log" I get this
So there is an error that stops the IIS to handle call #2, BUT it was still "completed successfully".
Any idea why it doesnt work?
The service is just getting a JSON package, that is split into different properties and then saved into a few rows of a database. Typically three rows.
It does not block the system, its just normal database development as far as I can see. Done by me thousands of times before....
Jun 12, 2020 06:50 AM|yij sun|LINK
Accroding to your description, I suggest you could add try catch outside the code.You need to debug the application to get a more specify cause of a 500 error.
Jun 18, 2020 11:31 PM|larka74|LINK
The problem I have is that my application is NOT called at all.
I have logs at the start, and try/catch around critical statements.
Nothing. I get nothing in my logs. The second call is just not absorbed.
The Failed Request Log is the only log where I get something, nothing in the regular Windows logs.
And I only get 500.
Googling I see that I should get a proper code like 500.x as you describe it above. But I only get 500.
I am totally lost.
This is a real challenge!
With two calls at the same time there should be allocated two threads from the threadpool?
My guess is that it might be something wrong there.
But I do not know...
Any ideas? Anyone?
Jun 19, 2020 04:57 PM|PatriceSc|LINK
You checked your IIS log? This is where you should find a 500.x code which might allow to better narrow down what happens.
Each request should be processed on its own. A common design issue is to use static data making both requests to share the same data and possibly fails (but for now this is just a guess).
Edit: for example https://stackify.com/how-to-interpret-iis-logs/, look at sc-status and sc-substatus