Hello.
It's happened we signed contract with one more new ISP. They give us one public IP and their GW.
Let it be 210.22.33.3, GW: 210.22.33.1
We have:
- RB450 connected
to LAN 192.168.5.0/24 (eth2 IP:192.168.5.3),
to I-net (eth1 IP: 209.11.22.3), GW is 209.11.22.1 - default GW for this router -- these are from the old one ISP.
- src-nat
/ip firewall nat
add action=src-nat chain=srcnat src-address=192.168.5.0/24 to-addresses=209.11.22.3
NOTE: simple masquerade is not appropriate here, because we have a server (mail, www, etc...) inside LAN which needs to be accessible from I-net, so we use dstnat/srcnat for some particular pairs of addresses like publicIP/local IP (209.11.22.2 <-> 192.168.5.54):
/ip firewall nat
add action=dst-nat chain=dstnat dst-address=209.11.22.2 to-addresses=192.168.5.54
add action=src-nat chain=srcnat src-address=192.168.5.54 to-addresses=209.11.22.2
..etc. (NOTE: 209.11.22.2 is secondary IP for eth1 of RB450 and there are some more public IPs configured on eth1 also the same way... I think it doesn't really matter...)
We need:
1. Connect our network to the 2nd new ISP in parallel
2. Distribute Internet traffic load 50/50 between these two different ISPs
3. Make our Internet connection fail-safe, so when one of two ISP connections is down all the Internet traffic 100% to be served by the second one.
Of course I've read the documentation, especially these two chapters:
http://www.mikrotik.com/testdocs/ros/2.9/ip/nat.php
http://www.mikrotik.com/testdocs/ros/2.9/ip/route.php
but it's not enough to solve my problem because of:
/ip firewall nat
add action=src-nat chain=srcnat src-address=192.168.5.0/24 to-addresses=209.11.22.3
-- it's clear that all the connection coming from LAN to be mapped to only one IP 209.11.22.3.
I was also trying to search trough this forum, but it seems there is no appropriate information to help me.
Please, Mikrotik gurus, give me a clue or an example how to solve my problem.
thank you in advance.