dcsimg
 

Tip of the Trade: Bandwidth Monitor NG

by Carla Schroder

Bandwidth Monitor NG is a simple bandwidth monitoring tool for Unix.

Bandwidth Monitor New Generation (bwm-ng) is a neat little console-based live bandwidth monitor for Linux, BSD, Solaris, Mac OS X, and any other Unix-type operating system. It watches any number of interfaces, and displays both individual and total statistics. bwm-ng is easy to use yet very useful. Output can be directed to ncurses, a plain console, a comma-delimited text file, or HTML, which is handy for remote monitoring.

This example is from a Linux router with two Ethernet interfaces:

$ bwm-ng
  bwm-ng v0.6-pre1 (probing every 0.500s), press 'h' for help
  input: /proc/net/dev type: rate
  |       iface                  Rx                   Tx                Total
  ===========================================================================
            lo:           0.00 KB/s            0.00 KB/s            0.00 KB/s
           lan:           2.13 KB/s           88.12 KB/s           90.26 KB/s
           wan:          88.12 KB/s            2.13 KB/s           90.26 KB/s
  ---------------------------------------------------------------------------
         total:          90.26 KB/s           90.26 KB/s          180.52 KB/s

That's pretty straightforward. This shows the incoming WAN link is nearly saturated. (By a Kubuntu dist-upgrade, in case you were wondering.) When you're wondering why a particular Web site is slow, bmw-ng might tell the tale — are fat pages that take forever to download the culprit? Or is the server slow? If your bandwidth is maxed out, it's not a server issue.

By default, bwm-ng updates itself every half-second. To change this interval, hit the + or - keys to increase or decrease the polling interval in 100ms intervals. Hit the letter "h" to see a help menu.

bwm-ng takes a long string of options to run in HTML mode. Give the output file, designated by the -F flag, any name you want. Then, point your browser to this file, which updates every second:

$ bwm-ng -o html -R 1 -H 1 -t 1 -D 1 -F bwm.html

Bwm-ng will run from a configuration file, so you don't have to tire your fingers with all that typing. See Gropp.org for more information.

This article was originally published on Tuesday Jun 6th 2006
Home
Mobile Site | Full Site