Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Community Member

Assigning a second external IP address to ASA 5505

Hi,

I have a working asa 5505 installation that I would like to configure for one more external IP address. My problem is when I try to create a second outside interface, called outside2 for example, i get an error message say that the subnet is overlapping with the previously configured outside interface. This probably makes sense but how do I assign a second, or even a third, external IP address to my asa.

Our ISP gave us five public addresses so I figured I'd use at least a few of them.

Thanx

2 REPLIES
Community Member

Re: Assigning a second external IP address to ASA 5505

I solved it my self.

The best way to assign multiple IP addresses to one interface is to use static nat.

For example:

static (inside,outside) x.x.110.250 192.168.1.250 netmask 255.255.255.255

static (inside,outside) x.x.110.251 192.168.1.250 netmask 255.255.255.255

Re: Assigning a second external IP address to ASA 5505

Hi Robert,

Just to correct perhaps minor typo, your current static entries that uses two different public IP addresses mapped to a single inside host of 192.1678.1.250 can only be possible through Policy NAT as it is not possible through static NAT to map two or more global addresses to a single inside host.

I think your static nat entry was meant to map a second public IP to a different host inside your LAN which is general practice when ISP hands out a block of public IP addresses for their clients to use.

Your static perhaps meant to be towards two inside hosts 192.168.1.250 & 251 or perhaps some other host other then 250.

static (inside,outside) x.x.110.250 192.168.1.250 netmask 255.255.255.255

static (inside,outside) x.x.110.251 192.168.1.251 netmask 255.255.255.255

Regards

784
Views
5
Helpful
2
Replies
CreatePlease to create content