Problem With Nat For An Special Range of IP

RouterOS General
1

Hello

I am using voip system for our company and i am using a voip provider for international calls.They wants their users to use their vpn to use the Server.
If i setup vpn on a desktop computer and use softphone its registering in thier system and everything is working fine.
Now i want to setup this vpn on my mikrotik router and use it as a route. I did it so now vpn is connected on mikrotik and i have added a new static route for the voip server but is like is not woking, i think it can send packets to server but for packets from voip server to me they can not route my device.
I had a senario like this before. Before more explain let’s call router on my side R1 and router on voip server side R2.
I solved that problem by add an static route to my network range on router R2.
But in this senario i don’t have access to R2 to do same configuration so i think i should nat my voip traffic on R1 to voip server, but i don’t know how exactly.

2

If you do this:

/ip firewall nat
add action=masquerade chain=srcnat out-interface=<vpn interface>

… all connections to server will get the address from your end of tunnel. And then just hope that the protocol won’t have any trouble with NAT.

3

Thank you for your help but i tried it, is not working.

4

Perhaps the protocol does have some problem with NAT and using VPN might be their way to avoid it. But if you put NAT in the way again… You’ll probably have to ask them. Or try to find and share some more details than “not working”.

5

put this near the top

chain=srcnat action=masquerade to-addresses=VOIP SERVER IP src-address=LAN IP/MASK dst-address=VOIP SERVER IP out-interface=VPN log=no log-prefix=""

Make sure the route you have configured is correct.