reduce-ip-addressing-errors-in-lab.html

---
url: /2008/02/reduce-ip-addressing-errors-in-lab/
title: "Reduce IP addressing errors in lab environment"
date: "2008-02-26T07:15:00.001+01:00"
tags: [ PPP,configuration,WAN ]
---

One of the most tedious tasks in the initial lab setup (at least for me) is the IP address configuration, which usually includes a number of typos and mixups on the WAN links. You can simplify then WAN address configuration if you configure only one end of the WAN link and let PPP do the rest. For example, you could use the following configuration to configure WAN link on your core router …<preclass="code">hostname Core-2<br/>!<br/>interface Serial1/0<br/> description link to POP<br/> ip address 10.0.2.1 255.255.255.252<br/> encapsulation ppp<br/> <classspan="high">peer default ip address 10.0.2.2</class></pre>… and use IPCP negotiation on the POP router to pick up the WAN IP address:<preclass="code">hostname POP<br/>!<br/>interface Serial1/0<br/> description link to Core-1<br/> <spanclass="high">ip address negotiated</span><br/> encapsulation ppp</pre><pclass="note">You should not <ahref="/2008/02/remove-unwanted-ppp-peer-route/">configure <strong>no peer neighbor-route</strong></a> on the router that gets dynamic IP address, as the subnet mask is not assigned with IPCP; you need the IPCP-generated host routes if you want to do hop-by-hop telnet between the routers.</p>