Port Forwarding -Help

RouterOS Beginner Basics
1

Hi Can you help me with a scenarion,

This is what i want to do,

  1. I want to connect 2 external WAN(internet links)
  2. Set up fail over for the two links. ( So only one works at any time. If the primary fails, an automated script will fail over to the secondary link)
  3. Port forward to an internal ISA server, which then relays POP3/SMTP traffic to a Mail server behind it on the internal LAN
  4. Maintain HTTP access at all times through this setup.

What i have managed to do so far is:

  1. I have manage to get the 2 WAN links connected, IP address & Routes are all in.
  2. Enable automated failover via Mikrotik System Script
  3. Port forwarding is proving to be a headache, see the following NAT rules and advise please :
    /ip firewall nat
    add action=dst-nat chain=dstnat comment=“” disabled=no dst-address=196.213.11.19 protocol=tcp to-addresses=10.0.0.2 to-ports=10025
    add action=dst-nat chain=dstnat comment=“” disabled=no protocol=tcp src-address=10.0.0.2 to-addresses=196.213.11.19 to-ports=10025
    add action=masquerade chain=srcnat comment=“” disabled=no

The first rule is supposed to forward traffic coming in on (public address) 196.213.11.19 port #10025 to internal ip 10.0.0.2 (ISA), the second rule to do the opposite. Third rule is supposed to take of ALL other traffic in and out of router?? ( Please assist if this thinking is correct) I can not get both DST-NAT and HTTP to work at the same time.

Calvin

2

add action=dst-nat chain=dstnat comment=“” disabled=no protocol=tcp src-address=10.0.0.2 to-addresses=196.213.11.19 to-ports=10025

That is supposed to be a srcnat rule like this (with a src-port):
add action=src-nat chain=srcnat comment=“” disabled=no protocol=tcp src-address=10.0.0.2 src-port=10025 to-addresses=196.213.11.19 to-ports=10025

The dstnat rule needs a “dst-port=10025” assignment also.

If you have two or more ips assigned to the same interface, you should also use a src-nat for the last rule action instead of a masquerade.