Having concern about the URI that is being reported in AppMon with 404 status code in error dash let.
Verified it via fiddler by doing actual actions & yes, it was showing in operation flow.
Now, this URI is no more appearing in fiddler as AM team have done some changes at application end.
Dilemma is, it is still showing in AppMon error dash let & count is very high. Now, I don't know where to check & what. Please guide me in this.
I would suggest you to right click on the error and drilldown to the purepaths and from the tree try to understand the method calling to this specific URI.
Right click on the method and open the details to know the reasons behind this error.
I would drill back from the error dashlet (or the purepath) to the User Action. What user Action is triggering this URL. Perhaps that can be useful to your investigation.
But I'm also not clear on your question. Are you trying to determine what is causing it? or where it is coming from? Does it help to right click on the top node of the purepath -> Details. This might give you some useful information.
Explaining the complete scenario here,
We first noticed from AppMon that, the error 404 count for Aspxpages/none is very high hence to verify it we checked fiddler trace & it was appearing there as well. (URI Aspxpages/none showing for IE browser only)
We informed AM team about the same & they have done some changes at back end.
The fiddler trace now not showing culprit URI. (After clearing history & cache of browser)
Now the issue is...In error dash let it is still showing noticeable error 404 count for that URI.
So is it the case that AppMon is showing inappropriate result? Because AM team has already fixed it & there should not be any error for that URI.
Have you noticed that AppMon also reports 4xx, 5xx, exceptions, error logs not just on the entry point (web server) agent but ALSO on the internal nodes?
Check this and let us know.
I see. In the attached snapshot I can see 3 "HTTP 404 Not Found" errors getting called per purepath so you need to consider 3 errors as 1.
Fiddler will capture only 1 4-Oh-4 error per request but others 404s are at serverside.
Also, I see another problem is chain of web servers are being invoked synchronously with high elapsed (response) time. This is quite high elapsed/response for such minor issue.
This is valid issue and should be reported for the review. Check if this is sort of heartbeat or poll request being invoked.
One catch here, I don't know whether my understanding is correct,
If we say the culprit URI is from server side then we should not see user actions with respect to it. Drill down to "visit" should not be visible but here in this case there 51 user actions & "visit" drill down is also available. Screenshot attached.