My take - you should be using both:

Example - 

<!-- this controls failure action on the dial-plan level -->

<action application="set" data="continue_on_fail=ALLOTTED_TIMEOUT"/> 

<!--the fail_on_single_reject is key here - it is at the call leg level and fails such that a second call is not pushed through to the fail-over carrier-->

<action application="bridge" data="{leg_timeout=10,fail_on_single_reject=ALLOTTED_TIMEOUT}user/1001|user2/1001"/> 

<action application="bridge" data="{leg_timeout=30,fail_on_single_reject=ALLOTTED_TIMEOUT}user/1002|user2/1002"/>  

So in this scenario - you have "continue_on_fail" to ensure that 1002 WILL BE called if 1001 times out, and fail_on_single_reject to ensure that 1001 will not be called a second time through the failover carrier.

​Phil

_________________________________________________________________________
Professional FreeSWITCH Consulting Services:
consulting@freeswitch.org
http://www.freeswitchsolutions.com

Official FreeSWITCH Sites
http://www.freeswitch.org
http://confluence.freeswitch.org
http://www.cluecon.com

FreeSWITCH-powered IP PBX: The CudaTel Communication Server
http://www.cudatel.com

FreeSWITCH-users mailing list
FreeSWITCH-users@lists.freeswitch.org
http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
http://www.freeswitch.org