Recently I decided to re-organise my bookmarks toolbar, and added links to my nagios and cacti installations. I noticed that the favicons where missing.

For cacti,there's a how to, but I found it a little over kill - I didn't need step 2 , as my catci install is an rpm from dag, and I didn't bother with step 4, as it worked without it, but hey ymmv!

Nagios was simpler, depending on how you installed nagios, will effect file permission , owners, directories etc. Again, I've got another dag rpm, so for me I logged in as root,

cd /usr/share/nagios/
wget http://www.nagios.org/images/favicon.ico

then edit index.html. just before \</head> , insert

<link rel="shortcut icon" href="/nagios/favicon.ico" type="image/x-icon" />

refresh your browser (delete the cache if necessary), and job done ! :D