Jun 212015

It was a while I did not post anything on this blog, so I will engage into something cool now 🙂

And into something I will need one day or another: a collection of very, very useful networking commands available for Linux.

Let’s start with an easy one: iperf and its variant with more options, netperf.
Very useful to measure TCP/UDP performances between two hosts by pumping traffic either mono or bidirectionally.
In the simplest usage, on one server you run iperf -s and get the following output:

$ iperf -s
Server listening on TCP port 5001
TCP window size:  128 KByte (default)


On the client, you run iperf -c <destination_host) -f m (this option is to get output in Mbps) and after few seconds you’ll see:

root@facchina:~# iperf -c -f m
Client connecting to, TCP port 5001
TCP window size: 0.02 MByte (default)
[  3] local port 48643 connected with port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-10.0 sec  1122 MBytes   941 Mbits/sec

 Rather cool, huh? And there are countless options…

The second one I’m sharing with you is tcptrack. Fantastic tool to keep track of the tcp connections happening on your machine and how much they are active. When you type tcptrack -i <interface> here’s what you get:



Let’s continue with bmon, specifically conceived to monitor interface traffic while keeping historical info in the view:



Another great one to detect programs eating bandwidth is nethogs, shown here below in a running sample:nethogs


And then, a really cool one I use VERY frequenty: iftop, to chech the bandwidth used by every connection on the machine.


To conclude this list of tools I selected speedometer, a very nice and clean tool to display network traffic information with quite many options

That’s all folks… enjoy!


Mar 212009

Made this small script for this purpose…

# Script to check a directory and write in file the new files
# since last check.
# Written by RoarinPenguin (
roarinpenguin@rottigni.net) on
21 march 2009
# Released under GPL License
# You need to create a file called lastcheck.time in same
# directory of this script

ADMIN="change to administrator email address"

> ./newfiles.list
echo "Last check for new files, done on "`date` >> ./newfiles.list
find $DIR2MON -maxdepth 5 -newer ./lastcheck.time >> ./newfiles.list
touch ./lastcheck.time