Here you can find some linux command line tools that can be used to monitor the network usage. These tools monitor the traffic flowing through network interfaces and measure the speed at which data is currently being transferred. Incoming and outgoing traffic is shown separately.
Some of the commands, show the bandwidth used by individual processes. This makes it easy to detect a process that is overusing network bandwidth.
1. Nload
Nload is a commandline tool that allows users to monitor the incoming and outgoing traffic separately. It also draws out a graph to indicate the same, the scale of which can be adjusted. Easy and simple to use, and does not support many options.
So if you just need to take a quick look at the total bandwidth usage without details of individual processes, then nload will be handy.
Installing Nload - Fedora and Ubuntu have got it in the default repos. CentOS users need to get nload from Epel repositories.
# fedora or centos
$ yum install nload -y
# ubuntu/debian
$ sudo apt-get install nload
- iftop
Iftop measures the data flowing through individual socket connections, and it works in a manner that is different from Nload. Iftop uses the pcap library to capture the packets moving in and out of the network adapter, and then sums up the size and count to find the total bandwidth under use
To Install iftop - Ubuntu/Debian/Fedora users get it from default repos. CentOS users get it from Epel.
# fedora or centos
yum install iftop -y
# ubuntu or debian
$ sudo apt-get install iftop
- iptraf
Iptraf is an interactive and colorful IP Lan monitor. It shows individual connections and the amount of data flowing between the hosts.
To install iptraf
# Centos (base repo)
$ yum install iptraf
# fedora or centos (with epel)
$ yum install iptraf-ng -y
# ubuntu or debian
$ sudo apt-get install iptraf iptraf-ng
Here is a screenshot :
- tcptrack
Tcptrack is similar to iftop, and uses the pcap library to capture packets and calculate various statistics like the bandwidth used in each connection. It also supports the standard pcap filters that can be used to monitor specific connections.
Install tcptrack - Ubuntu, Debian and Fedora have it in default repos. CentOS users need to get it from RepoForge as it is not available in Epel either.
# ubuntu, debian
$ sudo apt-get install tcptrack
# fedora, centos (from repoforge repository)
$ sudo yum install tcptrack
- Vnstat
Vnstat is bit different from most of the other tools. It actually runs a background service/daemon and keeps recording the size of data transfer all the time. Next it can be used to generate a report of the history of network usage.
$ service vnstat status
* vnStat daemon is running
Running vnstat without any options would simply show the total amount of data transfer that took place since the date the daemon is running.
Vnstat is more like a tool to get historic reports of how much bandwidth is used everyday or over the past month. It is not strictly a tool for monitoring the network in real time
Have a nice day........ :)
