New 506E can't change internal IP Address

[paulscofield]

I have just bought a new 506E. First thing was to change the internal address to 10.0.0.1

using either the PMD or the startup config GUI I cannot change the IP address! I get: "ERR, Internal address not on same subnet as DCHP"

This is strange because I am not using the internal DHCP server or client on either interface...

I have tried all combinations of enabling and changing, from only one thing to changing it all together.

Not an auspicious start to Cisco ownership!

If you can help I'd be grateful.

[bart_mason]

have you tried configuring via the console port with command line and a terminal emulator instead of the GUI/PDM?

I seem to recall this same symptom one time before and I think that the default configuration on the PIX may have the inside interface set to receive an IP address via DHCP.

If that is the case your inside address may be getting set by a dhcp server on your LAN and when you try to change the address to a different scheme it may not let you.

Try issuing a 'no ip address inside dhcp' command first then re-issuing the 'ip address inside 10.0.0.1' again and see if that helps... (from the console of course).

[paulscofield]

Actually the default was external=dhcp. The internal is fixed at 192.168.1.1 and I connected directly to a PC with a crossover (so no DHCP anywhere) - but all the same, I'll try your fix in about 11 hours when I get to the office in the UK.

Thanks for the help!

[scoclayton]

The issue is that the low end PIX's are pre-configured to work "out of the box" (assuming you want to use our addressing scheme). The reason you are unable to change the internal interface address is because we configured a DHCP server on the inside interface to serve addresses from the pre-configured internal subnet. The PIX will not let you shoot yourself in the foot and change the internal interface address to a subnet that is different than what we are handing out via DHCP. So, to fix this issue, you need to remove the DHCP pool of addresses from the PIX config and then change the interface address. The command to do this is:

[no] dhcpd address ip1[-ip2] if_name

(you can get these parameters from a 'sh run' on the CLI). A 'clear dhcpd' should also work if you want. You can also remove the DHCP pool via PDM but I am not real sure how (don't have one in front of me and I am a CLI guy). Once this is done, go ahead and change the interface address and re-configure the dhcpd commands if you want your PIX to serve addresses via DHCP to the internal clients.

Good luck.

Scott