How to set up multiple JVB without internal IP

I have 3 JVB servers inside a network without public IP, only the Jitsi Server with Jicofo, Prosody, etc, have one public IP with NAT. However my JVB only works if I attach a public IP with NAT to the server. How I can set just private IP for each JVB?

What do you mean with this? You should have 3 JVBs with 3 different private IPs with NAT through different ports (10000, 10001, 10002 etc) but all of them should populate the same external IP with different UDP ports

Yes, I have 3 JVB, each JVB with a different private IP, with internet access by NAT but without public IP. However the port is 10000 in all the servers, then how to change the port 10000 to other port? I have to add a note to this, I test with only one JVB and also no works.

set org.jitsi.videobridge.SINGLE_PORT_HARVESTER_PORT in /etc/jitsi/videobridge/ for each JVB and redirect incoming UDP traffic to the matching JVB

OK, I will to try.