## Learning about slightly more advanced networking with linux

Paul Warren

Mastodon: @pwarren@mastodon.thewarrens.name

email: paul at thewarrens.name

© 2021 Paul Warren

CC BY-NC-SA

## ! WARNING !

I am not a network engineer, there are gaps in my knowledge

The words I use might not be the correct ones

Please don't blame me if your network stops networking

Maybe don't go and try building an ISP based off this talk :)

## How it started

One subnet

Standard tech shop router with defaults

Made mistakes that broke critical applications

usual 192.168.0.0/24

Such as netflix and iview

## So where to from here?

linux can do VLANs, lets see if that helps!

It did!

## What even is a network

Ethernet?

Token Ring?

IPX?

AX.25?

## What even is a network

ipv4?

ipv6?

tcp?

Allows connections between computers

## Managed network?

Controls connections between computers

Scales connections between computers

Most of us probably work in a managed network

Diagram is nice, but hides complexities at each layer.

## Layers!

Like an onion!

That 7 layer thing from the OSI

Administrative overlays

VPNs/Tunnelled

or a parfait

which you can mostly ignore, as what we have doesn't conform to it. But it does provide a good framework for assisting understanding

## The Problems

VLAN

OSPF

more detail on what VLANs, OSPF and BGP are for
how to do these things in linux
intro to bird
more detail on bird
building out a virtual network with LXC
ergh, NAT
Why use a 'real' router
OpenWRT

## Resources

These slides: https://gitea.pwarren.id.au/pwarren/SysAdmin2022

bird: https://bird.network.cz

KNorrie's network examples: https://github.com/knorrie/network-examples

Openwrt: https://openwrt.org/

The OpenWRT IRC channel, currently on the OFTC network

BenEater's "Why was facebook down for five hours"