[Freeswitch-users] Is there a way to deal with "false ring-back than 503" carriers?

[Victor Chukalovskiy]

Hello,

A downstream carrier would accept INVITE, send 183 w/SDP, and almost 
instantaneously respond "503". This kills the call not letting re-route 
to the next carrier.

Without calling any specific names, this seems to become more common. 
Unfortunately, often the offending carrier is a few steps down the call 
path and I can't reach them with a cluebat.

Is there a way to make FS not fail the call and try the next route if 
using LCR as per below? Note that we are in bypass_media mode:

<action application="set" data="bypass_media=true"/>
<action application="bridge" data="lcr/lcr_profile/${destination_number}"/>

Or to keep it simple, forget LCR for a moment, can we make it go to 
gateway_2 in the following example if gw1 returns "183" followed by "503"?

<action application="set" data="bypass_media=true"/>
<action application="bridge" 
data="sofia/gateway/gw_1/${destination_number}|sofia/gateway/gw_2/${destination_number}"/>


Many thanks,
-Victor