Re: [Linphone-users] Strange Linphone Failure

[Stuart D. Gathman]

On Sat, 8 Jun 2019, Robert Dixon wrote:

> IPv4
> Private IPs.   192.168.*.*

I've only verified this for private IPv6, but one of the underlying 
libraries changed early this year to become rather prejudiced against
private IPs.  If any routable public IPs are available, it will try
to use those for SIP responses - ignoring the private IP you told it
to use.  If the public IP is actually routed to your destination (not
likely for your private IP4s, more likely for private IPv6), and
is allowed through firewalls, well and good (except if you
were counting on a VPN to encrypt things).  Otherwise, the call
setup fails, or works briefly before failing.

I haven't tested with IP4 (it's been obsolete for 15 years), but I
suspect the same thing happens with private IP4.

The work-around for me is to disable IP6 on the public (non-vpn) 
interfaces during the call.  That is likely more difficult for you,
as your VPN probably doesn't support layer 2 connections, and relies
on public IP4s to send/recv VPN packets.

If your private IP4s are assigned by a router, and you have no public
IPs on the PCs - then your problem is likely with router or firewalls
instead.

--
              Stuart D. Gathman <address@hidden>
"Confutatis maledictis, flamis acribus addictis" - background song for
a Microsoft sponsored "Where do you want to go from here?" commercial.