alert_actions.conf must be in the
default directory of the application you are using when you run the report/search that generates the alert.
This should work because when
http:// is specified it will take it literally...
hostname = http://xxxx.com
and if that doesnt work then this most certainly will:
hostname = http://xxxx.com:80
You can set it this way in the GUI if you have a search head cluster. It will replicate from one search peer to the others. You can set it in the GUI if you dont have search head cluster too.