DNCS-LAB | Assignment

Author: Davide Gagliardi Mat. 187521

University of Trento - Information and Communication Engineering

Description: This repository contains the Vagrant files and the scripts required to run the virtual lab environment used in the DNCS course.

Assignment: Based the Vagrantfile and the provisioning scripts available at: https://github.com/dustnic/dncs-lab the candidate is required to design a functioning network where any host configured and attached to router-1 (through switch) can browse a website hosted on host-2-c. The subnetting needs to be designed to accommodate the following requirement (no need to create more hosts than the one described in the vagrantfile):

Up to 130 hosts in the same subnet of host-1-a
Up to 25 hosts in the same subnet of host-1-b
Consume as few IP addresses as possible

Requirements

10GB disk storage
2GB free RAM
Virtualbox (https://www.virtualbox.org)
Vagrant (https://www.vagrantup.com)
Internet

Network map

VAGRANT
MANAGEMENT

 +------+
 |      |
 |      +---------------------------------------------+
 |      |                                         eth0|
 |      |           +--------+                    +--------+
 |      |           |        |                    |        |
 |      |       eth0|        |                    |        |
 |      +-----------+ROUTER 1+-------------------->ROUTER 2|
 |      |           |        |eth2            eth2|        |
 |      |           |        |                    |        |
 |      |           +--------+                    +--------+
 |      |               |eth1                           |eth1
 |      |               |                               |
 |      |               |eth1                           |eth1
 |      |       +-------v--------+                  +---v--+
 |      |       |                |                  |      |
 |      |   eth0|    SWITCH      |                  |      |
 |      +-------+                |                  |HOST C|
 |      |       |                |                  |      |
 |      |       +----------------+                  +------+
 |      |           |eth2     |eth3                    |eth0
 |      |           |eth1     |eth1                    |
 |      |       +---v--+  +---v--+                     |
 |      |       |      |  |      |                     |
 |      |   eth0|      |  |      |                     |
 |      +-------+HOST A|  |HOST B|                     |
 |      |       |      |  |      |                     |
 |      |       +------+  +-+----+                     |
 |      |                   | eth0                     |
 |      +-------------------+                          |
 |      +----------------------------------------------+
 +------+

Subnets

The network is divided in 4 different subnets:

A including host-1-a and router-1. The subnet is a /24 so you can get IP addresses for 254 different hosts (130 minimum required)
B including host-1-b and router-1. The subnet is a /27 so you can get IP addresses for 30 different hosts (25 minimum required)
C including router-1 and router-2. The subnet is a /30 so you can get IP addresses for 2 different hosts
D including router-2 and host-2-c. The subnet is a /30 so you can get IP addresses for 2 different hosts

VLANs

Two different VLANs allow router-1 to connect two different subnets via unique port. This two VLANs are marked with VIDs:

VID	Subnet
10	A
20	B

Interface-IP mapping

Device	Interface	IP	Subnet
host-1-a	eth1	10.0.10.1/24	A
router-1	eth1.10	10.0.10.254/24	A
host-1-b	eth1	10.0.20.1/27	B
router-1	eth1.20	10.0.20.30/27	B
host-2-c	eth1	10.0.30.1/30	C
router-2	eth1	10.0.30.2/30	C
router-1	eth2	172.16.255.253/30	D
router-2	eth2	172.16.255.254/30	D

Vagrant file and provisioning scripts

The project folder contains the Vagrant file, used to set up all the Virtual Machines, and the provisioning scripts for each VM.

All the VMs are based on Trusty64, an exception is made for host-2-c, based on Xenial64. This is because of a recent update of Docker, not supported by Trusty64's kernel.

Router 1

Router 1 is a VM based on Trusty64. Here the code used in the Vagrantfile to create the VM with two different interfaces.

  config.vm.define "router-1" do |router1|
    router1.vm.box = "minimal/trusty64"
    router1.vm.hostname = "router-1"
    router1.vm.network "private_network", virtualbox__intnet: "broadcast_router-south-1", auto_config: false
    router1.vm.network "private_network", virtualbox__intnet: "broadcast_router-inter", auto_config: false
    router1.vm.provision "shell", path: "router-1.sh"
  end

This code will execute the provisioning script named "router-1.sh"

The following lines are used to configure a trunk port for the VLAN:

  ip link add link eth1 name eth1.10 type vlan id 10
  ip link add link eth1 name eth1.20 type vlan id 20

Then is possible to assign IP addresses:

  ip addr add 10.0.10.254/24 dev eth1.10
  ip addr add 10.0.20.30/27 dev eth1.20
  ip addr add 172.16.255.253/30 dev eth2

Lastly the IP forwarding using OSPF

  sysctl net.ipv4.ip_forward=1
  sed -i 's/zebra=no/zebra=yes/g' /etc/frr/daemons
  sed -i 's/ospfd=no/ospfd=yes/g' /etc/frr/daemons
  service frr restart
  vtysh -c 'configure terminal' -c 'interface eth2' -c 'ip ospf area 0.0.0.0'
  vtysh -c 'configure terminal' -c 'router ospf' -c 'redistribute connected'

Router 2

Router 2 is a VM based on Trusty64. Here the code used in the Vagrantfile to create the VM with two different interfaces.

  config.vm.define "router-2" do |router2|
    router2.vm.box = "minimal/trusty64"
    router2.vm.hostname = "router-2"
    router2.vm.network "private_network", virtualbox__intnet: "broadcast_router-south-2", auto_config: false
    router2.vm.network "private_network", virtualbox__intnet: "broadcast_router-inter", auto_config: false
    router2.vm.provision "shell", path: "router-2.sh"
  end

This code will execute the provisioning script named "router-2.sh"

The following lines are used to configure IP addresses:

  ip addr add 10.0.30.2/30 dev eth1
  ip addr add 172.16.255.254/30 dev eth2

Then the IP forwarding using OSPF

sysctl net.ipv4.ip_forward=1
sed -i 's/zebra=no/zebra=yes/g' /etc/frr/daemons
sed -i 's/ospfd=no/ospfd=yes/g' /etc/frr/daemons
service frr restart
vtysh -c 'configure terminal' -c 'interface eth2' -c 'ip ospf area 0.0.0.0'
vtysh -c 'configure terminal' -c 'router ospf' -c 'redistribute connected'

Switch

Switch is a VM based on Trusty64. Here the code used in the Vagrantfile to create the VM with three different interfaces.

  config.vm.define "switch" do |switch|
    switch.vm.box = "minimal/trusty64"
    switch.vm.hostname = "switch"
    switch.vm.network "private_network", virtualbox__intnet: "broadcast_router-south-1", auto_config: false
    switch.vm.network "private_network", virtualbox__intnet: "broadcast_host_a", auto_config: false
    switch.vm.network "private_network", virtualbox__intnet: "broadcast_host_b", auto_config: false
    switch.vm.provision "shell", path: "switch.sh"
end

This code will execute the provisioning script named "switch.sh"

The following lines are used to set up a bridge (named switch) and add the interfaces to it (eth1 and eth2 are used for VLAN):

  ovs-vsctl add-br switch
  ovs-vsctl add-port switch eth1
  ovs-vsctl add-port switch eth2 tag=10
  ovs-vsctl add-port switch eth3 tag=20

Then the last command to set up ovs-system:

  ip link set dev ovs-system up

Host A

Host A is a VM based on Trusty64. Here the code used in the Vagrantfile to create the VM with one interface, connected to the switch.

  config.vm.define "host-1-a" do |hosta|
    hosta.vm.box = "minimal/trusty64"
    hosta.vm.hostname = "host-1-a"
    hosta.vm.network "private_network", virtualbox__intnet: "broadcast_host_a", auto_config: false
    hosta.vm.provision "shell", path: "host-1-a.sh"
  end

This code will execute the provisioning script named "host-1-a.sh"

The following line is used to configure the IP address on eth1:

  ip addr add 10.0.10.1/24 dev eth1

Then is possible to set a static route to router-1:

  ip route add 10.0.0.0/8 via 10.0.10.254

Host B

Host B is a VM based on Trusty64. Here the code used in the Vagrantfile to create the VM with one interface, connected to the switch.

  config.vm.define "host-1-b" do |hostb|
    hostb.vm.box = "minimal/trusty64"
    hostb.vm.hostname = "host-1-b"
    hostb.vm.network "private_network", virtualbox__intnet: "broadcast_host_b", auto_config: false
    hostb.vm.provision "shell", path: "host-1-b.sh"
  end

This code will execute the provisioning script named "host-1-b.sh"

The following line is used to configure the IP address on eth1:

  ip addr add 10.0.20.1/27 dev eth1

Then is possible to set a static route to router-1:

  ip route add 10.0.0.0/8 via 10.0.20.30

Host C

Host C is a VM based on Xenial64. Here the code used in the Vagrantfile to create the VM with one interface, connected to the router-2.

  config.vm.define "host-2-c" do |hostc|
    hostc.vm.box = "ubuntu/xenial64"
    hostc.vm.hostname = "host-2-c"
    hostc.vm.network "private_network", virtualbox__intnet: "broadcast_router-south-2", auto_config: false
    hostc.vm.provision "shell", path: "host-2-c.sh"
  end

This code will execute the provisioning script named "host-2-c.sh"

The following line is used to configure the IP address on enp0s8:

  ip addr add 10.0.30.1/30 dev enp0s8

Then is possible to set a static route to router-2:

  ip route add 10.0.0.0/8 via 10.0.30.2

Lastly the configuration of Docker to create a webserver based on Nginx and a webpage located in /docker-nginx/html directory.

  docker pull nginx
  mkdir -p ~/docker-nginx/html
  echo "<html>
  <head><title>DNCS ASSIGNMENT</title></head>
  <body>
  <p>So long, and thanks for all the fish.<p>
  </body>
  </html>" > ~/docker-nginx/html/index.html
  docker run --name docker-nginx -p 80:80 -d -v ~/docker-nginx/html:/usr/share/nginx/html nginx

First start

Install Virtualbox and Vagrant
Open the terminal and execute the command: git clone https://github.com/davidegagliardi/dncs-lab
You should be able to launch the lab from within the cloned repo folder.

  cd dncs-lab
  [~/dncs-lab] vagrant up --provision

Once you launch the vagrant script, it may take a while for the entire topology to become available.

Verify the status of the 6 VMs

  [dncs-lab]$ vagrant status  
  Current machine states:
  router-1                  running (virtualbox)
  router-2                  running (virtualbox)
  switch                    running (virtualbox)
  host-1-a                  running (virtualbox)
  host-1-b                  running (virtualbox)
  host-2-c                  running (virtualbox)

Once all the VMs are running verify you can log into all of them:

  vagrant ssh router-1
  vagrant ssh router-2
  vagrant ssh switch
  vagrant ssh host-1-a
  vagrant ssh host-1-b
  vagrant ssh host-2-c

To log out use the command exit

to test reachability log into host-2-c and try to ping host-1-b with ping 10.0.20.1

  [dncs-lab]$ vagrant ssh host-2-c
  vagrant@host-2-c: ping 10.0.20.1

and vice versa:

  [dncs-lab]$ vagrant ssh host-1-b
  vagrant@host-1-b: ping 10.0.30.1

Get the webpage from host-2-c with curl 10.0.30.1

  vagrant@host-1-b: curl 10.0.30.1

davidegagliardi / dncs-lab