Troubleshooting guide

dialer pool 1
ppp chap hostname <username>
ppp chap password <password>
ppp pap sent−username <username> password <password>
!
ip nat inside source list 1 interface dialer1 overload
!
ip classless
ip route 0.0.0.0 0.0.0.0 dialer1
access−list 1 permit <ip address of ethernet0> 0.0.255.255
!
Adjusting the PPPoE MTU Size on the PC Using the Dr. TCP Utility
To change the MTU size on the PC, follow the steps below. The registry change is saved when the procedure
finishes.
Note: The Dr. TCP utility is compatible with all Windows−based PCs.
Download the latest version of the Dr. TCP utility from http://www.dslreports.com/front/drtcp.html.1.
Refresh your browser page to ensure the page is current.2.
Run the Dr.TCP utility.3.
From the menu choose your Ethernet adapter.4.
In the MTU field, type 1492.5.
Click Apply to save the change, and then click Exit.6.
Reboot the PPPoE PC client.7.
You need to run the utility only once per PPPoE client PC.
Additional MTU Troubleshooting Steps
If you change the MTU size with Dr. TCP or on the Cisco DSL Router and are still not able to browse certain
web sites, adjust the MTU size again. Change the MTU size to 1452 in Dr. TCP, or change the MSS adjust
value on the Cisco DSL Router to 1412. If these sizes are too large, continue to lower the MTU sizes until you
reach a baseline of 1400 for Dr. TCP or 1360 for MSS adjust on the Cisco DSL Router.
Related Information
Cisco DSL Technology Support Information•
Cisco DSL Product Support Information•
Technical Support − Cisco Systems•
Contact the Cisco Technical Assistance Center
If you need additional assistance implementing PPPoE, contact the Cisco Technical Assistance Center (TAC).
Note: To use the Case Open tool to open a case online, you must be a registered user and you must be logged
in.
Call the TAC
Cisco DSL Router Configuration and Troubleshooting Guide