I want a quick way to check if any of the config settings on my 2820n have changed over a period of time (a week say).

What I thought should work (comparing the sha256 checksums of the 2 backups - if they're the same then the config file hasn't changed) doesn't work for all changes to config settings!

A counter-example: I backed-up the current config, then changed the HTTP port from 80 (the default) to 161, and backed that up (and logged-in to port 161 to check it worked - it did). To my surprise the 2 config files' SHA256 checksums were identical!

How can this happen?

My 2820n has firmware version 3.3.8_2471201.

Martin