Hi all,
I am the current maintainer of iftop for Debian GNU/Linux. In the past months and years users reported various bugs and feature requests for iftop and since I don't see that someone forwarded them upstream, I have made a short compilation of those outstanding issues. Feedback is much appreciated.
1. iftop does not notice changes to ppp interfaces and stops refreshing its output http://bugs.debian.org/543138
Iftop does not recognize changes to interfaces. If the interface goes temporarily down and then up again, iftop is not capable of recognizing the change and cannot display the traffic anymore. A manual restart is required to make it work again. It would be nice if iftop could detect such a change and continue with monitoring.
2. iftop: chooses eth0 as the default interface instead of the default route http://bugs.debian.org/644998
If the -i option is not specified, iftop looks for the first interface which is up and falls back to eth0 if none are found. On systems where two interfaces such as eth0 and wlan0 are up and the default route points to wlan0, iftop still chooses eth0 by default.
The code could be changed in two ways: * Only consider interfaces with routes associated with them. * Prefer the interface with a default route to other ones.
3. Add a command-line option to specify the Display Mode http://bugs.debian.org/511174
"Currently, the display mode can be toggled between "One line per host", "Received traffic only", "Sent traffic only" and "Two lines per host":
- either by pressing the "t" key, - or by setting the "line-display" parameter in the config file.
It would be very useful to have a way to specify this through a command-line option, like it's currently possible with most other frequently-used iftop adjustments."
4. Add a "min-bandwidth" option, so less resolution is wasted on logarithmic scale. http://bugs.debian.org/520386
"A "min-bandwidth" option analogous to the "max-bandwidth" option should be added. Currently the logarithmic display wastes a lot of space in the 0 - few-kilobytes-per-second range, which is often not useful (unless you're trying to examine intrusion attempts or something like that), causing the interesting range up to the maximum bandwidth to be crammed into just the right half of the screen. Being able to specify the minimum bandwidth to display would help a lot."
5. NAT support http://bugs.debian.org/631682
One user asked for NAT support for using iftop on a router to monitor traffic.
6. bar graph average should be an option in iftoprc http://bugs.debian.org/704813
The option "bar graph average (-B)" can be used within iftop but there is no corresponding option in iftoprc.
Thanks for reading
Regards,
Markus