Port-forwarding in RouterOS

#mikrotik #routeros #networking #portforwarding

[@supra107]

You can additionally limit the port forward to WAN in interface list, and if you have a dynamic IP you can make a simple script to pull your current public IP, as it'll be available somewhere in ROS, and save it/update it to an address list with a single entry. After that you set the Dst. address list to that list and now it's a pretty tight port forward rule. The only thing I need to figure out is how to probe local addresses to see if there's a service behind a port, so that the port forward rules can be dynamically turned on and off depending on the client status. Something like UPnP, but assigned manually, therefore safer.

[@supra107]

Well I found a good solution for that problem. Netwatch can do TCP port testing, and it can be used to dynamically turn port forwarding rules on and off. The only caveat is that it can only respond to TCP requests, so it can be used to toggle UDP access only if TCP is also used by the service.

[@P0ziii]

Yes i am also curious because i plan to use Failover on 3 WAN interfaces and for this i need dynamic port forwarding rule.

[@supra107]

@@P0ziii The dynamic address list trick seems to be the best. If you can get a script to fire depending on which WAN interface is up or down, you can have it pull your current public IP, update the address list with it, and the rest will click together. Scripting in ROS is it's biggest advantage. It needs a bit of learning but afterwards it becomes one of the most powerful tools at your disposal.

[@AndyChernov]

But input chain goes AFTER dst-nat in packet flow diagram. Why do you add accept rule in input?

[@mikrotik]

We fixed it, blame cupid

[@tcsoft]

Why not just "Dst. Address List: WAN" instead of "Dst. Address"?

[@erazelyou]

Doesn't DSTNAT before the Filter? Why use input not forward? After dstnat, the packet will have dst IP address of the host behind mikrotik, so it is a forward chain

[@mikrotik]

You are right, we fixed it

[@momensobhy2929]

Thank you for this awsome tutorial but i really need how to NTH load balance in routerOS v7 i treid so many times always somthing wrong please provide anything tell us how it works... thank you

[@m-electronics5977]

How you make that the winbox look so clear on Linux?

[@mikrotik]

Winbox let's you zoom in. If that doesn't help, you might have to look into wine settings, i.e. what font it uses.

[@m-electronics5977]

@@mikrotik I looked in there sometimes but I can't find something😫

[@m-electronics5977]

@@mikrotik But I find it good that you are using Linux😁

[@KenKenay]

easy