I've written a FAQ entry about an issue that's surprisingly more common than I originally thought, a missing avahi user and how it dramatically slows down webGUI usage.

 

There are 2 requests here:

- Determine if there is or was a defect that at some point in certain circumstances could or did cause the loss of the avahi info from the passwd and shadow files

- Detect on startup that the 'avahi' user is missing, and add the avahi user info to the passwd and shadow files, before the startup of the avahi daemon

I think this happens when someone upgrades from an very old, pre-avahi version of unRAID OS.

Moving to Defect Reports.

Note that the problem isn't limited to the avahi user.  My system was missing 7 users as compared to a fresh system:

  https://lime-technology.com/forum/index.php?topic=53052.0