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FastAGI

Implements the Asterisk Gateway Interface (AGI) over TCP sockets. This can help alleviate CPU load on your telephony server by relocating resource hungry scripts to another networked server. In order to instruct Asterisk to attempt a network connection, you must supply the hostname or IP address of the server where your FastAGI service is hosted and preface it with agi://:

exten => 5551212,1,AGI(agi://192.168.0.2)

Note that the agi:// syntax can be used with both the AGI and DeadAGI^? dialplan commands, while EAGI is currently not supported. The previous example instructs Asterisk to make a network connection to a host running on a local network server when the 5551212 extension is matched. By default, Asterisk attempts to connect to the specified server over port 4573. The port can also be specified should you choose to host the AGI service on another port: