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Next step is to indicate the FXO port(s) for Emergency calling (whether the call comes from a SIP endpoint or an FXS extension)
Simply click on the checkbox under ‘Handle Emergency Calls’ for the specific FXO port you wish to dedicate.
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What the above has done is create a dialplan routing rule to take care of emergency calls.
In ‘Expoert Config’, click on ‘Dialplan’. You will notice the extra diaplan called ‘Emergency_Call_Handling’
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Clicking on ‘Modify’ for this dialplan we can see what this dialplan does:
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