Monitoring Network Stats with vnstat

$ vnstat
Database updated: Tue Oct  7 14:30:01 2008

 eth0

    received:      13.54 MB (81.2%)
 transmitted:       3.67 MB (18.8%)
       total:      17.20 MB

                 rx     |     tx     |  total
 -----------------------+------------+-----------
     today     13.54 MB |    3.67 MB |   17.20 MB
 -----------------------+------------+-----------
 estimated        21 MB |       4 MB |      25 MB

To enable the monitoring, uncomment the following line from /etc/cron.d/vnstat

 */5 * * * *  vnstat /usr/sbin/vnstat.cron