Assigning two seperate ip ranges to an ASA firewall

Posted on 2012-09-10
Last Modified: 2014-02-02
Hey all,

We have hit a potential issue - we're running out of IP Addresses in the externally assigned range. We've spoken to Time Warner Cable who provide us with our Ethernet connection and they've said they can assign us an additional range, but it will not be sequential from the current range.

All fine with that, we don't really care - we just need more IP's.

How can i do this or Can this be done on a ASA 5520 version 8.3.(1)
Question by:cmitch2000
    LVL 14

    Accepted Solution

    I've been through this before, no problem.
    When your ISP assign new public IP addresses to you, it lets your data line (router) to route any packet to the added subnet: this means that your ASA will reach that (and can as well assign static NATs to its machines) new subnet through its default route.
    You can treat the new IPs as regular public IPs.

    hope this helps

    Expert Comment

    You need to make sure your ISP is routing the new  block  of public IPs to the IP address  assigned to the outside interface of your ASA firewall. Once that is done then you can use the new block issued and NAT just as your do with your original block.

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