Method 1 ------------------------------------------------------

The following config will allow the Linux machine (10.1.1.2) to read
the IP address from the DHCP interface on the Cisco router (eth0) as
user ddclient.  Since ddclient is configured with a priv level of 1 it
cannot do anything except look at the routers stats, ip addresses,
etc.  This should be pretty harmless even if ddclient's password were
to be discovered.

This has been tested with Cisco IOS 12.1(5)T5 running on a Cisco 2621
router.

Cisco Router Config (Assuming eth0 is DHCP interface)
-----------------------------------------------------
user ddclient password password
user ddclient priv 1
ip http auth local
ip http access-class 99
ip http port 1021
ip http server
access-list 99 permit host 10.1.1.2

DDClient Config
---------------------------------------------------
use=cisco, fw=10.1.1.1, if=eth0, fw-login=ddclient, fw-password=password


Method 2 ------------------------------------------------------

use=fw
fw=192.168.1.1/exec/show/interfaces/CR
fw-skip=FastEthernet0/0
fw-login=ddclient
fw-password=xxxxxxxx
