DSL connection using pppoe kernel-mode, HOW-TO

Authors: Fraaz.
Started on dec. 2004.

Introduction
Kernel configuration
Network card configuration
DNS resolvers configuration
Account settings
host.conf
Configuration file for pppoe
Running connection
Stopping the connection
Using a firewall

Introduction

This HOW-TO explains how to set up a DSL connection using the new kernel PPPOE support. The goal is to avoid installation of an external package (such as rp-pppoe) because it tends to be over-complicated, confusing, unreliable, outdated.

Kernel configuration

A proper kernel configuration, with of course ppp support and pppoe support - for example:

CONFIG_PPP=m
CONFIG_PPP_ASYNC=m
CONFIG_PPP_SYNC_TTY=m
CONFIG_PPP_DEFLATE=m
CONFIG_PPP_BSDCOMP=m
CONFIG_PPPOE=m

This can be set to 'y' instead of 'm', according to your needs. You can type grep -i ppp /boot/linux-`uname -r`.config to check you current kernel's options for ppp support.

It's important to remember that you can produce a custom kernel easily anytime using:
Nmake -gb linux-2.6 -p 'wipe install'.

Network card configuration

If you compiled the support of your network card directly in the kernel, nothing is required here.

If you compiled your network card as a kernel module, you must ensure to specify an alias like this in /etc/modprobe.conf

alias eth0 via-rhine

Ensure modules loading upon system booting by adding these lines in /etc/sysconfig/modules.d/site:

via-rhine
pppoe

You might also need to specify ppp_generic if you built it as a module

via-rhine is given as an example, replace it with the module name that corresponds to your hardware.
You possibly don't have /etc/modprobe.conf yet - create it !

Now here is the configuration required by the network init service. Edit /etc/sysconfig/network.d/ifconfig.eth0/ipv4:

ONBOOT=yes
SERVICE=ipv4-static
IP=192.168.1.1
GATEWAY=
PREFIX=24
BROADCAST=192.168.1.255

DNS resolvers configuration

Edit /etc/resolv.conf with the values provided by your ISP. This is an example for the French ISP Wanadoo:

search wanadoo.fr
nameserver 80.10.246.130 80.10.256.3

Account settings

Edit /etc/ppp/pap-secrets and /etc/ppp/chap-secrets:

"your_isp_login"       *       "password"

host.conf

Edit /etc/host.conf with:

order   hosts,bind
multi   on

Configuration file for pppoe

You must tell ppp to use the plugin rp-pppoe (installed with the ppp package) in /etc/ppp/options:

plugin rp-pppoe.so
name <your ISP login name>
noipdefault
defaultroute
mtu 1492
mru 1492
lock

Running connection

That's all, you are all done! To bring up the DSL line, just type:

pppd eth0

Stopping the connection

 /usr/sbin/pppd-stop

This command doesn't come with ppp, we added it for convenience, credits does to
http://casteyde.christian.free.fr/online/install_linux/book1.html

Using a firewall

Using a firewall is almost mandatory with DSL lines. Formerly rp-ppoe bundled firewall scripts, we discourage their use at the benefit of either a dedicated software, or our own firewall service 'nanofw' (we bundles it with iptables):

chmod +x /etc/init.d/runlevel.3/nanofw
# if you wan to setup NAT (connection sharing):
nano /etc/sysonfig/nanofw
# Edit the four values of the NAT section
# now run it:
telinit nanofw start