Hi Jon,

Thank you for your reply.
There seems to be some mis-understanding here.
I am looking for a tool wherein I can view download speeds of a particular user/ subnet.
iftop does provide me that but writing the output to a file is almost difficult to understand.

My requirement is not to know what the users are communicating.
Just the total download speed is what I am looking for, but for a particular user/ subnet.
vmstat gives me the WAN link download speed, but it does not solve my purpose.

Thanks and regards,
Shannon R

On Mon, Sep 24, 2012 at 9:38 PM, Jonathan Abbey <jonabbey@arlut.utexas.edu> wrote:
On Mon, 24 Sep 2012 10:51:08 -0500, Shannon Rodrigues wrote:
| Hi Jon,
|
| Thank you for your reply.
| In my typical setup, I want a tool which will display download rates of a
| particular user/ subnet. I am configuring download limiting rules to user/
| subnet but unfortunately have no tool to verify whether the config is
| working or not.

iftop doesn't know anything about what user is communicating, it just
shows what ports and IP addresses are involved.

| Manually checking output of iftop is helpful, but I would like to push the
| output to a file so that I could verify this at the end of the day. Getting
| it listed by ports is not a necessity. Traffic to and from will solve my
| purpose.
| I would like the output of download rate of a user/ subnet to be written to
| a file for lets say a 5 second interval.

Couldn't you use netstat (or ss, on more modern Linuxes) for that?  Or
tcpdump with some after the fact filtering?

iftop's claim to fame is real time curses-style graphing of traffic,
there are plenty of tools for doing statistics gathering that would be
more suitable for generating reports.

 Jon

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