After IOS upgrade, can't get globals/nats right.

Posted on 2004-11-19
Last Modified: 2010-04-10
Odd thing is, the original global/nat setup will not work with the new IOS. I am 99% sure it has nothing to do with the Access lists, but I can post them if needed.

Problem: With the new config, in the "library" which uses, if they check their outside ip from WHATISMYIP.COM or similar service, it shows up as In order for the DB application to work, their IP MUST show up as After an IOS upgrade and conduit conversion, the "original" config no longer allowed ANY internet access from the 10 range. After the changes, I was able to access the internet, but nothing else worked correctly (library had wrong outside ip).
The DMZ can be ignored for the time being.


ip address outside
global (outside) 1 netmask
global (dmz) 1
nat (inside) 0 access-list 108
nat (inside) 1 0 0 ("Library")
nat (inside) 1 0 0
nat (inside) 1 0 0 (All our client PC's are in the 10 range)
nat (dmz) 1 0 0
Cisco person changed to:

ip address outside
global (outside) 2 netmask
global (outside) 3 interface
nat (inside) 2 0 0 ("Library")
nat (inside) 1 0 0
nat (inside) 3 0 0 (All our client PC's are in the 10 range)
nat (dmz) 1 0 0

what am I doing wrong?
Question by:narcus
    LVL 36

    Accepted Solution

    Hi narcus,
    You shouldn't specify the netmask in the 'global' command. I suspect it is being ignored so the second command is being used which is the interface of the PIX. Paste the following into the configuration :-

    no global (outside) 2 netmask
    no global (outside) 3 interface
    global (outside) 1
    LVL 2

    Author Comment

    Thank you, that could have solved the problem. I will apply that as soon as i can today and let you know.

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