Simple bandwidth monitoring on Linux

If you want a simple lightweight tool to monitor the network traffic in and out of your server vnstat might be just what you need. It keeps hourly, daily and monthly records and provides simple estimates of your expected use, it is also easy to link up to a web based frontend for fancy charts and reporting.

Installing and configuring vnstat is very simple, firstly install using your standard package manager, for example:

Debian

apt-get install vnstat

CentOS:

yum install vnstat

Then tell vnstat to create a database for the network interfaces you want to listen to (e.g. eth0):

vnstat -u -i eth0

That’s it, wait a few minutes then run vnstat to view a simple console display of the amount of traffic that has traveled though all the interfaces you’re monitoring:

vnstat
 
   eth0 since 01/22/12
 
          rx:  177.59 MiB      tx:  7.78 MiB      total:  185.37 MiB
 
   monthly
                     rx      |     tx      |    total    |   avg. rate
     ------------------------+-------------+-------------+---------------
       Jan '12    177.59 MiB |    7.78 MiB |  185.37 MiB |    0.59 kbit/s
     ------------------------+-------------+-------------+---------------
     estimated       183 MiB |       7 MiB |     190 MiB |
 
   daily
                     rx      |     tx      |    total    |   avg. rate
     ------------------------+-------------+-------------+---------------
     yesterday     12.53 MiB |    1.36 MiB |   13.89 MiB |    1.32 kbit/s
         today      8.28 MiB |     127 KiB |    8.40 MiB |    0.88 kbit/s
     ------------------------+-------------+-------------+---------------
     estimated        --     |      --     |      --     |

You can also get vnstat to dump its output in a programming friendly format (semicolon delimited):

vnstat --dumpdb

If you do want a nicer looking interface or one that doesn’t require shell access have a look at: vnstat PHP frontend

If you need a bandwidth monitoring solution that records the utilization of individual protocols instead of just received and transmitted traffic then have a look at bandwidthd