Tip for troubleshooting in IIS - finding your requests

I spent some of my day today investigating some performance problems with a website hosted in IIS6.

The problem was that this was a live site that received several thousand hits a day. I wanted to be able to quickly find my specific requests in the IIS log.

My solution?  Give my browser its own User Agent string.  That way I can search for my specific entry in the appropriate log file.

I was using Firefox for this investigation.  It's fairly easy to change your User Agent string:

  • Go to about:config in the address bar of Firefox
  • Right-click in the window and choose New | String.
  • Call the Preference Name, "general.useragent.override" and set the Value to something you'll recognise.  It's usually safer to take your existing User Agent string (which you can find at http://whatsmyuseragent.com/) and just append something unique.
  • Go to http://whatsmyuseragent.com/ and make sure your change has persisted.
To undo your change later, just return to about:config and delete your override entry.

Now when looking through the IIS logs, you can just search for your specific User Agent string to find your entries.

Tip: See here for instructions on changing your User Agent in Chrome, and here for some help in IE 8.

Damian Brady

I'm an Australian developer, speaker, and author specialising in DevOps, MLOps, developer process, and software architecture. I love Azure DevOps, GitHub Actions, and reducing process waste.