Hi all,
I have been asked to develop a web page that regroup the statistics data from multiple asterisk servers.
In other words, I have to regroup on the same page how many trunks are up, how many users are online, how many active calls on multiple servers.
Is there a way to get this data directly from the gateway?
If not, how to get this data from each server?
Thank you,
Take a look at Nagios/Icinga, if you still need to re invent the wheel then try it with AMI commands.
THis is helpful. Thank you good sir/m’am!
Otherwise, is there a way I can get this info/data by using the REST API ?
Sir definitively Sir 
Seems like yoiu have some nice commands to work with:
https://wiki.asterisk.org/wiki/display/AST/Asterisk+13+ARI
https://wiki.asterisk.org/wiki/display/AST/Asterisk+13+Channels+REST+API
The only thing here is to secure your app and all asterisk must be +13v