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bradatohnyx
bradatohnyx
New Member
October 8, 2020
Question

Single WAN IP, VoIP vendor requires 1 to 1 NAT, more than just VoIP service needs to pass

  • October 8, 2020
  • 1 reply
  • 2953 views

I have a FortiGate 60E

OS v6.0.4 build 0231

Single WAN IP address

Multiple services on multiple internal hosts (VoIP + web services) port forwarded currently (and working for the most part)

VoIP (3cx) vendor wishes to enable webRTC

It is not working - 1 way audio

Seems to be NAT issue with webRTC - fortigate IP LAN IP address is being substituted for WAN which 3CX says is the problem

 

Is there a way to configure my port forwards so that I can allow VoIP webRTC to work, and still have web service port forwards, on a single WAN IP address?

Or is 1 to 1 NAT only way to achieve this type of NAT behaviour on a fortigate?

 

Thanks,

 

Brad

    1 reply

    fcb
    fcb
    Visitor III
    October 9, 2020

    I'm not sure if I fully understand that but your internal voip solution will have to have the same NAT'ed WAN address if the traffic is inbound or outbound of the network since you've only got one WAN IP. Maybe the are saying the traffic in ingressing the network one way and exiting another (still with the same WAN IP) but the only way that I know of to get ya true one to one NAT is to remove any port forwarding information - Just contact your ISP and get a small .29 - money well spent.

     

    If there is no option to increase the IP space then I'd say remove all of the other PAT's and setup their gear with a 1 to 1. Does it correct the issue? If so, go get new ISP. If not, move everything back by restoring the backup you just took.

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