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Best way of setting up ASA5505 for my home dsl use

Hi all

I have a cisco asa 5505 firewall, and I have a normal home ADSL broadband router, the router currently connects via wireless to my pc.

What I would like to do is basically connect the asa to my pc, then my router to my firewall.

what the best thing to do here, run the asa in transparent mode, OR routed mode and do NAT on the firewall to the private ip address range of my router.

OR, would it be possible to get the outside interface of my asa to get DHCP from my broadband router so it will use a 192.168.1.x address on the outside, and then turn NAT off?



Hall of Fame Super Silver

Best way of setting up ASA5505 for my home dsl use

Your ASA can get its outside address via DHCP from your ADSL router

     hostname(config-if)# ip address dhcp

...and still NAT your inside network (inside = something other than to outside "interface" IP address. Your router will NAT again to its public IP.

Community Member

Best way of setting up ASA5505 for my home dsl use

Hi Carl,

Since ASA5505 is a little different in Architecture(switched) from other ASA appliances, I would recommend you to first properly configure the interfaces on the ASA.

The above link will help you with that.

ASA can be configured as DHCP client.

To obtain an IP address from a DHCP server, enter the following command:

hostname(config-if)# ip address dhcp [setroute]

where the setroute keyword lets the ASA use the default route supplied by the DHCP server.

Reenter this command to reset the DHCP lease and request a new lease.

If you do not enable the interface using the no shutdown command before you enter the ip address dhcp command, some DHCP requests might not be sent.

Also look at the Getting started guide

Please post if any further clarification is needed.


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