Configuring inside interface with different IP/Subnet

Posted on 2007-10-10
Last Modified: 2012-05-05

I have an ASA 5505 that I'm setting up. I need to give the inside interface a different subnet ( I've been using the console port to make changes (db9/COM1) from the factory defaults. The problem is when I change the subnet I get locked out from using the ASDM via a LAN port and CAT5, and the DHCP server stops working though I configured it with the new subnet. I can access the firewall just fine via LAN port when it's at factory default, and DHCP works fine as well.

What should I do? thanks!

Question by:Trevor Local
    LVL 57

    Accepted Solution

    COnnect viar COnsole cable like you have been doing

    Enter config terminal mode

    conf t

    Allow the new subnet ASDM access

    http 255.255.25 inside

    then change the inside IP address

    int vlan1
    ip address

    save your work

    write mem

    noy you can access the firewall with an IP on the new subnet :)

    LVL 57

    Expert Comment

    by:Pete Long
    Basically you need to add the new subnet (or IP) to allow ASDM access before you change the inside IP address :)

    Author Comment

    by:Trevor Local
    thanks Pete! that was it.
    I had to disable DHCP first, before I changed the interface subnet.

    Let the games begin!! I'm sure you'll see more questions from me....
    LVL 57

    Expert Comment

    by:Pete Long
    >>I had to disable DHCP first, before I changed the interface subnet.

    Ah that old chestnut :)

    Glad you got there - ThanQ

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