Hello list, I'm experimenting a "strange" issue with FreeSWITCH. If I Start Freeswitch from command line: *freeswitch -nonat -nf* IPv4 internal profile working fine: * sofia status* Name Type Data State ================================================================================================= external-ipv6 profile sip:mod_sofia@[2001:19f0:9002:11f6:5400:1ff:fe64:1503]:5080 RUNNING (0) 45.77.161.19 alias internal ALIASED external profile sip:mod_sofia@45.77.161.19:5080 RUNNING (0) external::example.com gateway sip:joeuser@example.com NOREG internal-ipv6 profile sip:mod_sofia@[2001:19f0:9002:11f6:5400:1ff:fe64:1503]:5060 RUNNING (0) internal profile sip:mod_sofia@45.77.161.19:5060 RUNNING (0) ================================================================================================= If I use script daemon *systemctl start freeswitch* with this parameters: *-nonat -nf -nc* I have this error: Error Creating SIP UA for profile: internal (sip:mod_sofia@45.77.161.19:5060;transport=udp,tcp) The likely causes for this are: 1) Another application is already listening on the specified address. 2) The IP the profile is attempting to bind to is not local to this system sofia status Name Type Data State ================================================================================================= external-ipv6 profile sip:mod_sofia@[2001:19f0:9002:11f6:5400:1ff:fe64:1503]:5080 RUNNING (0) external profile sip:mod_sofia@45.77.161.19:5080 RUNNING (0) external::example.com gateway sip:joeuser@example.com NOREG internal-ipv6 profile sip:mod_sofia@[2001:19f0:9002:11f6:5400:1ff:fe64:1503]:5060 RUNNING (0) ================================================================================================= I compiled 1.6 version from source (git) on CentOS 7.4. Remote VPS with Public and Private IPv4 Any Hint? Thank you Regards -- --- I'm SoCIaL, MayBe