Matt-J.co.uk : Ramblings

Once again, many days have gone by, and no posts. There is still a LOT of stuff i need to blogify, but with current coursework, work, placement presentations and other such joyous stuff, I just have not had the time..

This however, required a mention!
On saturday, Martin was telling me about the features of the switch he has bought (L3 Gigabit, 3com, pretty nice)  and mentioned it supported OSPF. As mine, Martins and Daves crazy LAN topologies are linked using VPN’s, I have been wanting to impliment some dynamic routing for a while (As having to add eachothers routes when someone decides they need a new subnet is VERY tedious)

So out came quagga (emerge quagga) an implimentation of OSPF2 (and rip2, ospf3, ripng, bgp) for *nix.
Martin would also have to run this on his debian tunnel endpoint, however the OSPF area could then be extended to the switch, allowing his L3 switch to become his default gateway for his lan, and dynamically know where all our subnets were, even if one of us added a new one without telling anyone else.

The config started out slow, with me printing the quagga docs (hate reading on a screen), but these turned out to be more a command reference than a guide, and so we busked it.

A couple of minor routing loops later:

• One because we had not removed the static routes for each other before enabling OSPF.
• The second because OSPF was distributing my locally terminated public IP that martin’s VPN connected down, and so OpenVPN at his end saw this local route to my public IP, and tried to send the tunnel establishing UDP packets down it’s own tunnel interface.. which soon collapsed in on itself :P.
  I soon noticed this with wireshark and masked OSPF from advertising that route.

After this, everything worked! and many repetitions of ‘epic win’ were enjoyed.

Today, we contacted dave and got him quagga’d up.. This time the whole process took maybe 10 mins, including firewall rules for daves OSPF traffic (i’m a little paranoid)

Updates of subnets accross the whole atonomous system are sub second. This rocks!

If anyone wants my notes on ospf quagga setup please let me know.

It works!!

In other news today, it snowed here in fleet. Looky:

That’s all for now, off to do some more coursework :(

//Matt