All of a sudden we are seeing this random error / exception in our web application.
Failed to load resource: the server responded with a status of 502 (Bad Gateway).
In the Log Stream, we are seeing the following details, with specific error code as 502.3 - Bad Gateway: Forwarder Connection Error (ARR).
Also, sometimes in the browser itself we see "The CGI application did not return a valid set of HTTP errors." getting displayed.
Most of the searches for these error codes refer to "IIS / Proxy Server" configuration. But, we haven't changed any such settings.
The error happens very randomly and not specific to any user action/function. Same functionality works first and on second execution immediately after first one throws this error.
How to figure out what is causing this and how to fix?
I google this question, because the program was normal at the beginning, and the subsequent 502.3 error. After I checked the information on the Internet, I feel that it can only give us an inspiration, and it cannot solve your problem immediately.
So my suggestion is that first you browse post1 and post2 I provided.
Next, proceed to Troubleshoot according to the steps of the official documentation. Specific errors require specific analysis.
Related
With some Uploads in Moodle (3.9) Uploads are not successful, mainly pdf.
The message that comes up is: "An error occured whilst communicating with the server".
not successful requests show
POST /course/dndupload.php undefined
successful requests show
POST /course/dndupload.php HTTP/1.1
When a pdf is reexported with libre office for example the same pdf can be uploaded without problems.
any ideas?
Is the LibreOffice pdf smaller? It could be PHP timing out.
https://docs.moodle.org/311/en/File_upload_size#Modifying_the_php.ini_file
What is the value for max_execution_time ? You can check the PHP values here -
Site administration > Server > PHP info
Also, try switching debug to developer level and see what the error message is.
Site administration > Development > Debugging
Debug messages = Developer
Display debug messages = checked
Although be cautious changing the debug level if its a production site. If you have access to the config.php file then you can specify a user.
// You can specify a comma separated list of user ids that that always see
// debug messages, this overrides the debug flag in $CFG->debug and $CFG->debugdisplay
// for these users only.
// $CFG->debugusers = '2';
Thanks for the response, in the meantime a solution to the problem was found. On the server a measurement against log4j2-vulnerability has been implemented: https://support.f5.com/csp/article/K59329043#proc2. This caused the misbehaviour, the iRule has been removed, now it works again.
We have a test website that uses Persits ASPPDF to build a PDF using the ImportFromUrl method. It works fine on our test domain, but when I use the same code on another domain (and crucially perhaps, a sub-domain) I get the "MSXML2::ServerXMLHTTP Error: The request has timed out." error.
This leads me to think its related to the problem outlined in
https://support.persits.com/show.asp?code=PS080709171
"the calling Active Server Page (ASP) should not send requests to an ASP in the same virtual directory or to another virtual directory in the same pool or process. This can result in poor performance due to thread starvation."
So perhaps the config of the two servers hosting the two sites (test and live) are different - and if so what would that be? - Or you can't run this method on a sub-domain? Any guidance out there please?
I've had the same issue for weeks and finally found out what the problem was. In my case, it was because I had set to True the options that allow the debug of classic ASP code, without which I could not debug using visual studio. Setting those options back to False fixed the issue.
The website URL works fine. The link from google maps on the phone works fine. For some reason when you google it in the browser (mobile browser or desktop) you get an Internal Service Error. Google said it was nothing on their end to be done.
Has anyone encountered this or have an idea of what's causing it? The error received is below.
Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.
Please contact the server administrator and inform them of the time the error occurred, and the actions you performed just before this error.
More information about this error may be available in the server error log.
Apache Server at www.thetechbuyer.com Port 80
As the error suggests, an Internal Server Error is internal to your webapp or web service on your host. It usually means that your program, whatever it is doing, has crashed. This could be because of misconfiguration, or a bug in your code, or something else - without knowing more (possibly a lot more) about your server environment, it is impossible to know what.
Check your server logs - they should have more information.
(It also isn't clear what this has to do with Google+.)
I've seen hundreds of pages explaining how to create custom error pages in Apache 2 server. My question is different. I have a web application running in Apache (it is a ISAPI DLL, but it could also be a CGI executable). My application can handle internal server errors and generate a detailed error message (for instance, include a full stack trace), included in the response together with error code 500. AFAIK, Apache just let me use redirection in order to display custom error messages: http://httpd.apache.org/docs/2.2/custom-error.html
HTTP spec (RFC 2616 - section 10), not only allows but also recommend that detailed error message should be included in the BODY section of the response in case of error code > 500.
Link: http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5
Seems that Apache won't let my custom error message go to the browser, and always replace it with its own internal error message and I believe that it is not the correct behavior, based on RFC 2616.
So my question is: Is there any setting in Apache server that will let my custom message go to the browser? Or, is there anything that can be done in my application that will instruct Apache to send my custom error message (something like some specific header field in the response)?
More on the subject:
When my ISAPI application returns error code 500, with other error information in the response body, Apache replaces it with its standard "500 Internal Server Error" message/HTML content, and inside Error.log file I can see the "useless" "Premature end of script headers" message. I'm deeply sure that my headers are fine, including the Content-Type field.
If I replace the 500 error code with any other server error code (e.g. 501) it works flawlessly and my response goes to the browser as is. The same header is sent to the Apache server, only the error code is different (501, instead of 500). With this test result in mind, one of these two must be true:
1- Apache requires some specific header field when status code is 500
2- Apache won't let custom error messages with status code 500 go to the browser.
I don't see any other alternative.
I think you're conflating two questions. You can generate a 500 response with a CGI script and include your custom body. Or you can override any 500 with any resource you want.
If you're failing to do the former, it's likely because of some subtle thing in the ISAPI interface between Apache and your module. Desk-checking the code says you should be able either set the pseudo
Status: 500
Header, or basically return any ISAPI error and end up with a 500 and your custom body.
Apache has two notions of a status code -- the one in the status line (r->status) and an error code returned separately from the module that handles the request (return HTTP_INTERNAL_SERVER_ERROR, return r->status).
When the former is used as the latter is when the custom error messages get lost. All of that happens in./modules/arch/win32/mod_isapi.c in Apache. Whatever is going on, it is ISAPI unique.
I have problem with WCF on IIS when using diagnostics.
When I call the service I get the following error:
System.Net.WebException: The remote
server returned an error: (500)
Internal Server Error..
If I remove "system.diagnostics" section I dont get error 500 but I get an error
The requested service,
'http://localhost/CustomerServiceSite/Customer.svc'
could not be activated. See the
server's diagnostic trace logs for
more information..
Which obviously needs diagnostics to get fixed.
Any idea why diagnostics doesnt work?
Check event log on web server - http 500 should be logged there. Also check that Account running your AppPool in IIS has access rights to file used for diagnostics.
The diagnostics will write a trace file to disk - maybe the user account WCF/ASP.NET is running under doesn't have permissions to write the file.
If I opened my service in browser (http://localhost/CustomerServiceSite/Customer.svc) I have seen the whole error.
The problem was becouse I used NHibernate and Diagnostics in wrong way. Commenting NHibernate configuration solved my problem.