Enable IPv6
We have for first IP: fe80::f816:3eff:fe6c:23fe
ipv6 will be also automatically picked and used by harvester, but this is not true:
root@vps556404:~# netstat -tulpn | grep 443
tcp 0 0 54.37.204.4:443 0.0.0.0:* LISTEN 882/nginx: master p
tcp6 0 0 51.38.117.249:443 :::* LISTEN 829/java
The tcp6 above is a IPv4-mapped IPv6 address.
JVB 2019-03-26 07:48:14.845 INFO: [27] org.ice4j.ice.harvest.AbstractTcpListener.addLocalAddresses() Not using link-local address /fe80:0:0:0:f816:3eff:fe6c:23fe%ens3 for TCP candidates.
Adding org.ice4j.ice.harvest.ALLOWED_ADDRESSES=51.38.117.249,fe80::f816:3eff:fe6c:23fe
results in
JVB 2019-03-26 07:44:16.584 WARNING: [27] org.ice4j.ice.harvest.HostCandidateHarvester.initializeAddressFilters() Failed to add an allowed address: 51.38.117.249,fe80::f816:3eff:fe6c:23fe JVB 2019-03-26 07:44:16.800 WARNING: [27] org.jitsi.videobridge.IceUdpTransportManager.log() Failed to initialize TCP harvester on port 443: java.net.UnknownHostException: 51.38.117.249,fe80::f816:3eff:fe6c:23fe: invalid IPv6 address. Retrying on port 4443. JVB 2019-03-26 07:44:16.803 WARNING: [27] org.jitsi.videobridge.IceUdpTransportManager.log() Failed to initialize TCP harvester on fallback port 4443: java.net.UnknownHostException: 51.38.117.249,fe80::f816:3eff:fe6c:23fe: invalid IPv6 address
So the OVH VPS seems not to have IPv6 correctly configured.