The main objective of [RARE / FreeRouter 101] series is to help you getting started with FreeRouter from scratch without any prior knowledge.

Requirement

  • Basic Linux/Unix knowledge
  • Basic networking knowledge

Overview

freeRouter is a free, open source router control plane software. For nostalgic and networkers from prehistoric era (like me), freeRouter besides Ethernet, is able to handle HDLC, X25, frame-relay, ATM encapsulation. Since it handles packets itself at the socket layer, it is independent of underlying Operation System capabilities. We will see in the next articles how freeRouter subtlety leverage this inherently independence to connect different data-plane such as OpenFlow, P4 and other possible data-plane that would appear in the near future.

The command line tries to mimic the industry standards with one exception:

  • no global routing table: every routed interface must be in a virtual routing table
  • positive side effect: there are no vrf-awareness questions

Article objective

This article is meant to simply deploy 2 instances of freeRouter on the same fresh linux installed linux box. We are voluntary using freeRouter (freerouter.nop.hu) "raw" official repository in order to get familiar with the deployment manual process. Even if the deployment process is straightforward, it is not self explanatory for people non familiar with java/linux.

In order to simplify the deployment we have automated freeRouter daily builds on:

But let's get our "hand dirty" and follow the simple manual installation. 

Diagram

[ #001 ] - Cookbook

In our example we will use a genuine debian stable image (buster) installed as a VirtualBox VM.

  • Start & connect your VM as root 
  • Update your VM
apt-get update
apt-get upgrade

In this example, we won't recompile freeRouter so installing headless java runtime is enough. This set up is recommended for production environment in order to ensure minimal software footprint

apt-get install default-jre-headless --no-install-recommends

Let's create the following structure, even if some folder are empty for now:

mkdir -p ~/freeRouter/bin ~/freeRouter/lib ~/freeRouter/etc ~/freeRouter/log
cd ~/freeRouter/lib
wget http://freerouter.nop.hu/rtr.jar

so you have have the following environment:

╭─[11:11:54]floui@debian ~ 
╰─➤ tree freeRouter
freeRouter
├── bin   # binary files      
├── etc   # configuration files      
├── lib   # library files      
└── log   # log files

FreeRouter uses 2 configuration files in order to run, let's write these configuration files for R1 in ~/freeRouter/etc

freeRouter hardware file: r1-hw.txt
int eth1 eth 0000.1111.0001 127.0.0.1 26011 127.0.0.1 26021
tcp2vrf 1123 v1 23
freeRouter software configuration file: r1-sw.txt
hostname r1
!
vrf definition v1
 exit
!
int eth1
desc r1@e1 -> r2@e1
vrf forwarding v1
 ipv4 address 1.1.1.1 255.255.255.252
 ipv6 address 1234::1 ffff:ffff:ffff:ffff::
 exit
!
server telnet tel
 security protocol telnet
 no exec authorization
 no login authentication
 vrf v1
 exit
!

Repeat the same configuration for R2 in ~/freeRouter/etc

freeRouter hardware file: r2-hw.txt
int eth1 eth 0000.2222.0001 127.0.0.1 26021 127.0.0.1 26011
tcp2vrf 2223 v1 23
freeRouter software configuration file: r2-sw.txt
hostname r2
!
vrf definition v1
 exit
!
int eth1
desc r2@e1 -> r1@e1
vrf forwarding v1
 ipv4 address 1.1.1.2 255.255.255.252
 ipv6 address 1234::2 ffff:ffff:ffff:ffff::
 exit
!
server telnet tel
 security protocol telnet
 no exec authorization
 no login authentication
 vrf v1
 exit
!
freeRrouter launch with blank parameters
╭─[12:58:45]floui@debian ~/freeRouter  
╰─➤  java -jar ./lib/rtr.jar 
java -jar ./lib/rtr.jar <parameters>
parameters:
  router <cfg>            - start router background
  routerc <cfg>           - start router with console
  routerw <cfg>           - start router with window
  routercw <cfg>          - start router with console and window
  routers <hwcfg> <swcfg> - start router from separate configs
  routera <swcfg>         - start router with sw config
  test <cmd>              - execute test command
  show <cmd>              - execute show command
  exec <cmd>              - execute exec command
R1 launch with supplied r1-hw.txt and r1-sw.txt with a console prompt
╭─[12:59:11]floui@debian ~/freeRouter  
╰─➤  java -jar lib/rtr.jar routersc etc/r1-hw.txt etc/r1-sw.txt 
info cfg.cfgInit.doInit:cfgInit.java:556 booting
info cfg.cfgInit.doInit:cfgInit.java:680 initializing hardware
info cfg.cfgInit.doInit:cfgInit.java:687 applying defaults
info cfg.cfgInit.doInit:cfgInit.java:695 applying configuration
info cfg.cfgInit.doInit:cfgInit.java:721 done
welcome
line ready
r1#
R2 launch with supplied r2-hw.txt and r2-sw.txt with a console prompt
╭─[12:58:52]floui@debian ~/freeRouter  
╰─➤  java -jar lib/rtr.jar routersc etc/r2-hw.txt etc/r2-sw.txt
info cfg.cfgInit.doInit:cfgInit.java:556 booting
info cfg.cfgInit.doInit:cfgInit.java:680 initializing hardware
info cfg.cfgInit.doInit:cfgInit.java:687 applying defaults
info cfg.cfgInit.doInit:cfgInit.java:695 applying configuration
info cfg.cfgInit.doInit:cfgInit.java:721 done
welcome
line ready
r2#

Verification

R1 telnet access from Virtualbox VM guest via port 1123
╭─[1:09:28]floui@debian ~  
╰─➤  telnet localhost 1123
Trying ::1...
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
welcome
line ready
r1#
R2 telnet access from Virtualbox VM guest via port 2223
╭─[1:15:37]floui@debian ~  
╰─➤  telnet localhost 2223                                                                                                                                           1 ↵
Trying ::1...
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
welcome
line ready
r2#
R1 running configuration
r1#sh run                                                                      
hostname r1
buggy
!
!
vrf definition v1
 exit
!
interface ethernet1
 description r1@e1 -> r2@e1
 vrf forwarding v1
 ipv4 address 1.1.1.1 255.255.255.252
 ipv6 address 1234::1 ffff:ffff:ffff:ffff::
 no shutdown
 no log-link-change
 exit
!
!
!
!
!
!
!
!
!
!                  
!
!
!
!
server telnet tel
 security protocol telnet
 no exec authorization
 no login authentication
 vrf v1
 exit
!
!
end

r1#
R2 running configuration
r2#sh run                                                                      
hostname r2
buggy
!
!
vrf definition v1
 exit
!
interface ethernet1
 description r2@e1 -> r1@e1
 vrf forwarding v1
 ipv4 address 1.1.1.2 255.255.255.252
 ipv6 address 1234::2 ffff:ffff:ffff:ffff::
 no shutdown
 no log-link-change
 exit
!
!
!
!
!
!
!
!
!
!                  
!
!
!
!
server telnet tel
 security protocol telnet
 no exec authorization
 no login authentication
 vrf v1
 exit
!
!
end

r2#
Ping from R1 -> R2
r1#ping 1.1.1.2 /vrf v1                                                        
pinging 1.1.1.2, src=null, cnt=5, len=64, tim=1000, ttl=255, tos=0, sweep=false
!!!!!
result=100%, recv/sent/lost=5/5/0, rtt min/avg/max/total=1/2/3/13
r1#
r1#ping 1234::2 /vrf v1                                                        
pinging 1234::2, src=null, cnt=5, len=64, tim=1000, ttl=255, tos=0, sweep=false
!!!!!
result=100%, recv/sent/lost=5/5/0, rtt min/avg/max/total=1/4/11/23
r1#
Ping from R2 -> R1
r2#ping 1.1.1.1 /vrf v1                                                        
pinging 1.1.1.1, src=null, cnt=5, len=64, tim=1000, ttl=255, tos=0, sweep=false
!!!!!
result=100%, recv/sent/lost=5/5/0, rtt min/avg/max/total=0/1/2/12
r2#    
r2#ping 1234::1 /vrf v1                                                        
pinging 1234::1, src=null, cnt=5, len=64, tim=1000, ttl=255, tos=0, sweep=false
!!!!!
result=100%, recv/sent/lost=5/5/0, rtt min/avg/max/total=0/1/3/7
r2#
Initiate IPv4 telnet from R1 -> R2 (inside freeRouter scope)
r1#telnet 1.1.1.2 23 /vrf v1                                                   
 - connecting to 1.1.1.2 23

welcome
line ready
r2#
Initiate IPv6 telnet from R2 -> R1 (inside freeRouter scope)
r2#telnet 1234::1 /vrf v1                                                      
 - connecting to 1234::1 23

welcome
line ready
r1#

Conclusion

In this article you:

  • had a brief introduction of freeRouter networking Swiss army knife
  • learn how to deploy 2 instances of freeRouter and interconnect them via 2 UNIX sockets on a VM guest running on VirtualBox 
  • this setup is ideal, for network simulation encompassing hundreds of nodes, self contained in the same VM without interaction with the external world. (protocol experimentation, convergence test etc.)

[ #001 ] RARE/FreeRouter-101 - key take-away

  • FreeRouter is using UNIX socket in order to forward packet.

This is a key feature that will be leveraged to connect freeRouter control plane to any type of data-plane

  • In FreeRouter everything is in a VRF (so there is no global VRF)

This design choice has very positive consequences like: No VRF awareness questions,have multiple bgp processes for the same freeRouter instance (each bound to a different VRF) 

All the feature set is IPv4 and IPv6 compliant. So there is no compromised !