Debian Problem With PPPOE and Static IP

I’m abusing my blog with an appeal for help; all those who aren’t Debian experts in a helpful mood can skip over this one.

My ISP requires that I connect with PPPOE for some reason or another; my Debian-box gateway has been doing this fine for some months. Because we do a bit of low-grade web serving, we’ve arranged for a static IP address. I’m having the dickens of a time getting it to work. Right now, my /etc/network/interfaces looks like this:

# /etc/network/interfaces -- configuration file for ifup(8), ifdown(8)

# The loopback interface
auto lo
iface lo inet loopback

# The first network card - this entry was created during the Debian installation
auto eth0
iface eth0 inet dhcp

So I fixed the etho0 like so, where 1.2.3.4 is the new static IP (although I think with PPP in the way it doesn’t make any difference:

iface eth0 inet static
  address 1.2.3.4
  netmask 255.255.255.0

/etc/ppp/peers/dsl-provider used to look like this (stripped comments):

user tbray

pty "/usr/sbin/pppoe -I eth0 -T 80 -m 1412"

noipdefault
defaultroute

usepeerdns

hide-password
lcp-echo-interval 20
lcp-echo-failure 3
connect /bin/true
noauth
persist
mtu 1492

All I did was replace the noipdefault with 1.2.3.4: per (I thought) the man page. When it comes up now, ifconfig says it has the right IP address, but I can’t ping anything or get anywhere. I poked around in /var/log/* and indeed there a various grumblings with ppp in them in logfiles here and there, but my eye isn’t educated enough to figure out which might be significant.

If someone comes back to me on this one, I’ll post the solution here, and the Google visibility here at ongoing is good enough that it should be easy to find for other people with the same problem.

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