Please delete this topice

RouterOS General
1

Please delete this topice.

2

Wouldn't some simple action=dst-nat chain=output NAT rule do what you need for the client part? and for the server part, action=dst-nat chain=dstnat rules?

4

If there are only a few L2TP clients, we can change the port using DNAT.

But,
what if there are 500 L2TP clients?
What if there are 1,000 L2TP clients?
and using 500+ 1000+ dst-nat rules?

5

And, what is the difference? If you have 1000 L2TP clients, you already have 1000 entries under PPP -> Interfaces to manage.

And for the L2TP server, you can even have one single DSTNAT action=dst-nat chain=dstnat dst-port=10000-20000 to-ports=1701 rule for your 10000 of choosable ports.

6

IPLC/IPEL Server
200.200.200.200

200.200.200.200:10001-10010 --> l2tp-server public ip 1 ( 10001-10010 redirect 1701 )
200.200.200.200:10011-10020 --> l2tp-server public ip 2 ( 10011-10020 redirect 1701 )
200.200.200.200:10021-10030 --> l2tp-server public ip 3 ( 10021-10030 redirect 1701 )
...
200.200.200.200:19991-20000 --> l2tp-server public ip 999 ( 19991-20000 redirect 1701 )
...

Now all I need to do is add the L2TP custom port option.
Managing and maintaining such a large L2TP client using dst-nat rules is really terrible.

7

I know that dst-nat can change ports; the topic of this post is requesting the addition of this feature.

/ip firewall nat add action=dst-nat chain=output dst-port=1701 protocol=udp to-ports=10001

8

Write this request directly to MT support, there are low chances that it will be noticed here on the forum.