UPDATE
sorry I forgot to mention, but on all routers you have to add the following line into
your /etc/rc.d/rc.local file.
echo "1" > /proc/sys/net/ipv4/ip_forward

Hello everyone,

Ever got tired of adding those routes by hand, ever wonder if there is a easier way to do this all ?
Well the solution is a nice piece of software called Quagga (http://www.quagga.net/). In this guide
I will show the most simple dynamic routing you can do with this software.

Let's imagine that our network has for example 4 routers. Each of these routers have 3 subnets.



All of these Routers either have CentOS 3.x or CentOS 4.x installed of them.

ROUTER 1 :

eth0 : 192.168.0.250
eth1 : 192.168.1.250
eth2 : 192.168.2.250
eth3 : 192.168.20.10

ROUTER 2 :

eth0 : 192.168.3.250
eth1 : 192.168.4.250
eth2 : 192.168.5.250
eth3 : 192.168.20.11

ROUTER 3 :

eth0 : 192.168.6.250
eth1 : 192.168.7.250
eth2 : 192.168.8.250
eth3 : 192.168.20.12

ROUTER 4 :

eth0 : 192.168.9.250
eth1 : 192.168.10.250
eth2 : 192.168.11.250
eth3 : 192.168.20.13

On Router 1 you do the following.



then you edit the configuration files

/etc/quagga/ripd.conf
/etc/quagga/zebra.conf

like this

/etc/quagga/ripd.conf



/etc/quagga/zebra.conf



then you make sure zebra and ripd starts during startup




On Router 2 you do the following.



then you edit the configuration files

/etc/quagga/ripd.conf
/etc/quagga/zebra.conf

like this

/etc/quagga/ripd.conf



/etc/quagga/zebra.conf



then you make sure zebra and ripd starts during startup



On Router 3 you do the following.



then you edit the configuration files

/etc/quagga/ripd.conf
/etc/quagga/zebra.conf

like this

/etc/quagga/ripd.conf



/etc/quagga/zebra.conf



then you make sure zebra and ripd starts during startup



On Router 4 you do the following.



then you edit the configuration files

/etc/quagga/ripd.conf
/etc/quagga/zebra.conf

like this

/etc/quagga/ripd.conf



/etc/quagga/zebra.conf



then you make sure zebra and ripd starts during startup




now you can configure a client for example in LAN1 like this

ip : 192.168.1.10
netmask : 255.255.255.0
default gw : 192.168.1.250
dns : ip_you_use_for_that

and from this one client in LAN1 , you will be able to ping all the other clients in LAN2,LAN3,LAN4,LAN5,LAN6,LAN7,LAN8,LAN9,LAN10,LAN11,LAN12.

If you want to see what actualy happens on a router when zebra and ripd are working do the following :



this will return the following



for the password you type zebra and press enter

then you type


and something like this (this is only a EXAMPLE here from another server, so you wont get this exactly, but it is still important for you to see , the most interesting thing is those routes with a R>* in front of them, it means that quagga is doing it's job)



This is it. You can use quagga in more complex networks, or less complex one, even with 2 routers it makes life easier...


Sincerely
Robert B

This post has been edited by Robert83: Oct 3 2005, 04:56 AM