On Monday I moved to a new broadband provider (A&A). The BT Openreach guy turned up and swapped over the face plate on my master socket, dropped off the FTTC modem, then went and down to the green box in the street and flipped my connection over. It all would have been very uneventful except for the small problem that the new router I needed to link my kit up to FTTC modem had not arrived.
This is because BT messed up the address for where they think my line is installed a few of years ago and I’ve not been able to get them to fix it. A&A quickly sent me out a replacement router with next day delivery but it would mean a effectively 2 days without any access at home.
The routers talks to the FTTC modem using a protocol called PPPoE over normal ethernet. There is a Linux package called rp-pppoe which provides the required support. So to quickly test that the install was working properly I installed this on to my laptop and plugged it directly into FFTC modem. Things looked really good but did mean I was only able to get one device online and I was tied to one end of the sofa by the ethernet cable.
PPPoE is configured the same way PPP used to be used with dial up modems, you just need to create /etc/ppp/pppoe.conf file that looks a bit like this:
ETH=eth0 USER=xxxxxxx DEMAND=no DNSTYPE=SERVER PEERDNS=yes DEFAULTROUTE=yes PING="." CONNECT_POLL=2 CF_BASE=`basename $CONFIG` PIDFILE="/var/run/$CF_BASE-adsl.pid" LCP_INTERVAL=20 LCP_FAILURE=3 FIREWALL=NONE CLAMPMSS=1412 SYNCHRONOUS=no ACNAME= SERVICENAME= CONNECT_TIMEOUT=30 PPPOE_TIMEOUT=80
And include you username and password in the /etc/ppp/chap-secrets. Once set up you just need to run pppoe-start as root
In order to get back to something like normal I needed something else. I had a Raspberry Pi in my bag along with a USB Ethernet adapter which looked like it should fit the bill.
I installed rp-pppoe and the dhcp server then plugged one ethernet adapter into the FTTC modem and the other into a ethernet hub. Into the hub I had a old WiFi access point and the rest of my usual machines. After configuring the Pi to masquerade IP traffic from the hub I had everything back up and running. The only downside is that speeds are limited to 10mbps as that is as quick as the built in ethernet adapter on Pi will do.