Dialing extension on a remote Asterisk Server through IAX trunk

Open the config extensions_additional.conf

Go to the context of the concerned IVR.

add the Line

exten => _<Dial Pattern>,1,dial(iax2/<Trunk Name>/${EXTEN})

eg: exten => _5xxx,1,dial(iax2/OFFICE3/${EXTEN})
When this is done, a pattern with 5 followed by 3 digits ,ie, an extension will be forwarded to the remote asterisk server using IAX2 trunk

So that an extension of an elastix server can be dialled from a remote server.

Once the file is edited

Reload asterisk.