What could cause a '503 - Service Unavailable' HTTP error when requesting element log files? On one of our systems, we are facing this error for all elements, also when directly browsing to the log file URL while being logged in to the DataMiner server which is hosting the element.
The problem persists after restarting both IIS and the DataMiner Agent.
This could be caused by many reasons, most likely a configuration/installation issue. To find the root cause, this has to be further investigated:
- Does it show this error only when accessing viewlog.asp, or also when opening other web pages, for example Reporter?
- In Windows' Roles and Features, is "ASP" installed?
- Are there more error details in the logging of IIS? (C:\inetpub\logs\LogFiles)
- Are there any related errors in the logging of Windows?
Then it could be an issue with:
– The SLAuthFilter ISAPI filter. You could temporarily remove this ISAPI filter from IIS Manager, but don’t forget to add it back as otherwise it exposes several webpages as it removes the authentication checks.
– The virtual directory “logging” might not work correctly. Could be tested by requesting a log file via the url: http://localhost/logging/sldataminer.txt
Is this happening on a Windows Server 2016 Version 1709?
If so, this KB of Microsoft might help you out: https://support.microsoft.com/en-us/help/4050891/error-http-503-and-was-event-5189-from-web-applications-on-windows-10
Thanks Bert.
This is happening on a Windows Server 2019 (clean DMA install).
Just to be sure, I removed the temp files described in the linked KB article, but saw no change afterwards.
Thanks Wim.
– Reports and Dashboards ASP pages are opening up fine.
– ASP has been installed
– IIS logs the GET requests to open the URL, but all looks clean there. No error messages
– Windows Event Log looks pretty clean. No obvious errors.
Note that this is occurring for every DMA in the cluster (recent clean installs on Windows Server 2019).