Download the archive and unpack it

wget http:///session6.zip
unzip session6.zip

The archive contains the follosing files

• ubuntu.img - the virtual machine's disk
• prepare.sh - the script for setting up the virtual machine
• iperf_client.sh - launches multiple streams using iperf
• iperf_server.sh - listens on multiple sockets using iperf

Install the necessary packets

sudo ./prepare.sh prepare

Boot up the virtual machine

sudo ./prepare.sh start

Open SSH consoles to the virtual machine

ssh root@192.168.0.2

Run a simple netperf test

netperf -H 192.168.0.2

• What is the bandwidth of the virtual link?
• How does netperf run? On the virtual machine, check the TCP listening ports

  netstat -tlpn

  Which options are available to the netperf users?

  netperf --help

  The user can choose from a series of tests. Which are them?

  man netperf

  Run a 2 seconds UDP request-response test and display the CPU usage for both the host and the virtual machine

  netperf -H 192.168.0.2 -t UDP_RR -l 2 -cC

Measure bandwidth and delay on links towards California and Spain

http://speedtest.net

Ping the following hosts

192.168.0.2
cs.curs.pub.ro
gnu.org

Compare the latencies and verify the number of hops along each way using traceroute.

Browse the Web for a few random pages. Do you find the response time acceptable? What does a browser do when you type a web page's address? Which DNS server are you using? Try resolving a random hostname. What is the query time?

dig ampathos.ro

Edit /etc/resolv.conf to use Google's DNS instead of your ISP's DNS. Add the following line at the top of the file.

nameserver 8.8.8.8

Try resolving ampathos.ro again. Is the query time better? Surf the web. Is the lag significant? Revert your nameserver changes.