Using a Cisco T-1 Router as a bridge

Posted on 2006-05-01
Last Modified: 2013-11-29
Here is the equipement I have:
Cisco T-1 Router
SonicWall Firewall / VPN Appliance

Here is what I need to do:
I need a way to get the Public IP address(s) that I have directly to the SonicWall WAN port.  The ISP has given me a block of about 7 IP addresses.  I know that the first one has to be the gateway, but I am able to use the others.  

Here is what I need to know:
What kind of code do I need to put in my Cisco Router to get it to just pass all traffic directly to the SonicWall?  I basically just want to make my router into a bridge that will connect my ISP's network directly to my SonicWall.  I have done this with DSL routers that allow you to use bridge mode.  I understand that it will not longer be routing, but the firewall can handle all of the NAT.  
Question by:doulos777
    LVL 10

    Expert Comment

    What are the IP Addresses given by your ISP ? Did he give you a serial IP Address and also a block of IP Addresses?
    LVL 3

    Accepted Solution

    On each of the interfaces add the command (via console or telnet)
    interface eth1
    bridge-group 1

    then under global config mode add

    bridge 1 protocol ieee

    The sonic will have to complete the authentication to the isp.
    LVL 3

    Expert Comment

    sorry also add
    no ip routing
    LVL 2

    Expert Comment

    Have you tried adding a static route?

    ip route [network inside your sonicwall] [subnet mask of that network] [wan adress of sonicwall]

    someting like this:  ip route [whatever adress you use on the sonicwall]

    The address for the wan port on the firewall has to be one of the public addresses. This command says to reach any ip adress in the /24 go through your Sonicwall (which should have NAT turned on)


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