LAN Traffic monitoring

[sunhux G]

I'm looking for a way to monitor the traffic load, ie rate of traffic going
in
& out of a specific NIC on my RHES 4.6.

Thought of using a script to take consecutive readings, say every 5
seconds by taking the difference in the RX & TX readings & then
divided by 5 to get the rate.

Which of the following outputs are most up-to-date & accurate :
ifconfig bond0  (ie issue this command 5 secs apart, get the difference
                       & divide by 5)
netstat -i bond0  (ie issue this command 5 secs apart, get the difference
                       & divide by 5)
  OR
cat /proc/net/dev


"ethtool -S bond0" on my server gave  "no statistics available".


If anyone has a script (Shell or Perl) to share, appreciate if you can
email it over


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