Routing problem

ISP provide me with two IP address for ADSL router ( linksys G-ADSL ) subnet for ADSL assign automatically on router by ISP subnet to add to firewall network interface
 ADSL router have private IP address with NAT enable

I need to connect ADSL router to firewall .
I will assign the following IP address to eth 2 on Firewall :
with sub interface as eth2.1 .
what static route I should add on ADSL router to be able to forward traffic from firewall to ADSL router then to internet

can you help
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If NAT is enabled, you cannot add the public IP ( to the firewall because the ADSL router is "hiding" the private ( network behind it.

I would assign an address of to Eth2 on the firewall and the configure the ADSL router (if it has the function) to make the firewall the DMZ host, i.e. it will pass all traffic that it cannot "handle" to the firewall.

With regards to routing, the PC's on the inside on the firewall cobnnected to Eth1 (which will have to be on a different network again e.g. will then have the Firewall as the Default gateway.  It turn the Firewall will have the ADSL router as it's Default Gateway.  The ADSL router will have it's gateway assigned by the ISP.
salmaaloufAuthor Commented:
I will disable NAT on ADSL router .
Forget about PC its not important .
IF I put IP address on eth 2 of firewall with public IP address

ADSL router already have public IP address assign by ISP
on WAN side with IP address  on LAN side.

what static route I should add to routing table of ADSL router to forward traffic from firewall to ADSL router
Note : ADSL router connect directly to Firewall through Ethernet cable no other connection between .
As per the attached file, you could try to add the following route to the ADSL router.  Th eroute will look like this (if written in "Windows" notation):

route add MASK -p

I do however have doubts whether it will work.Visual representation of config
The Lifecycle Approach to Managing Security Policy

Managing application connectivity and security policies can be achieved more effectively when following a framework that automates repeatable processes and ensures that the right activities are performed in the right order.

The proposal above is correct

Network MASK nexthop

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salmaaloufAuthor Commented:
I am able to add the static route now I am checking with local ISP to ensure my gateway IP address .

Hi Netminder,

I am not satisfied with the points allocation.


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