I just received the 871 and attempted to set it up; it replaces a Nexland Pro400 router. I've got Cox internet, they've told me that I don't need a username or password to get an ip addr from their server. On interface Fa4, I specified 'ip addr dhcp client-id FastEthernet4' and have added the ip addresses of the Cox nameservers. But Fa4 still does not obtain an ip address. I don't know what I've missed, any clues?
The router has IOS v870-advsecurityk9-m, version 12.4(4)T7 installed.