IIS 7 and Above
How do we debug a “This service is unavailable” error message for our...
Last post Apr 28, 2019 04:15 AM by Rovastar
Apr 08, 2019 06:02 PM|kmg_software|LINK
We've recently had an issue where our application/website was displaying "The service is unavailable" message to users. Please note it wasn't the typical message where it displays the 503 error code that IIS typically generates...the only text on the page
was "The service is unavailable" (it did not show any error codes or any additional text).
We stopped the application pool and started it back up, and the site began to work again. It was down for approximately 15 minutes.
We've gone through all of the log files and interestingly enough there was some traffic going to the server during the 15 minutes we were seeing the "The services is unavailable" message, without any 503 attempts being logged, no windows event errors, etc.
Does anyone have any ideas how to isolate the issue or find a log file that would display what happened?
Apr 08, 2019 07:03 PM|Rovastar|LINK
Often 503 error are not set via IIS but via the HTTP API before it gets to IIS.
Things like a too busy/stopped/crashed/rapid fail protected app pool will result in the HTTP API responding with a 503 as it cannot find any web in IIS to serve content.
To start with look in your HTTP.SYS log here:
and lookup the reason for the errors her:
Apr 27, 2019 01:56 PM|arvindsinghu|LINK
Internet Information Services (IIS) uses a highly efficient and flexible logging architecture. When an event is logged, it uses the relevant logging module. You can use the log files to analyze a wide range of issues, along with the demographics and
usage of the IIS.
How to Read & Customize IIS Log Files
Apr 28, 2019 04:15 AM|Rovastar|LINK