Routerboard configuration on RB450 required

[rakeshmikrotikindia]

We have two lines at one of our network sites one is from Airtel (E1 - Primary line ) with 16 Public IPs and other is from BSNL which is normal broadband connection. We want to configure both lines of auto failover with NAT. If primary line goes down then secondary should take over automatically.

Below network diagram will help you to understand our network setup.
(See the attachment picture)

We want to NAT all public IPs in the below listed manner so that servers in our internal network can be accessed from outside using Airtel public IPs. However it is not possible when the primary like (Airtel) goes down but internet should work on servers.


Trust, above requirement is clear.

Please have a look & advice us for the configuration on RB450

[Chupaka]

for NAT, it will like that:

/ip firewall nat add chain=dstnat dst-address=125.19.186.0/28 in-interface=Airtel-Internet action=netmap to-addresses=192.168.200.0/28
/ip firewall nat add chain=srcnat src-address=192.168.200.0/28 out-interface=Airtel-Internet action=netmap to-addresses=125.19.186.0/28
/ip firewall nat add chain=srcnat src-address=192.168.200.0/28 out-interface=BSNL-Internet action=netmap to-addresses=192.168.1.0/28

for failover, you may look at http://wiki.mikrotik.com/wiki/Advanced_Routing_Failover_without_Scripting - but probably you may use simplier way, it depends on your Airtel connection type