Scheduling iftop

Sir Prised · 07-01-2014, 12:29 PM

Hi

I want to run iftop from 0800 until I shutdown some time later in the day.
The simple root command is /usr/sbin/iftop -i em1 which opens it in a terminal window.

How do I create that as a root cron job.. i.e.
0 8 * * * /usr/sbin/iftop -i em1 does nothing.

Do I have to create a script for the cron job to initiate?
As you can tell, I'm out of my limited depth !

Thanks

unSpawn · 07-01-2014, 12:58 PM

For one offs this may be easier:

Code:

echo '/usr/sbin/iftop -n -N -i em1 -t'|/usr/bin/at 08:00

Note iftop uses ncurses to display data and that may not be what you want, hence the "-t".
Once you kill the job an email will be sent with all the logged data in it.
If that isn't what you want or need then see 'man tcpdump' and capture data first and parse it later.

Sir Prised · 07-01-2014, 01:22 PM

Thanks for the reply.

Entering something first thing is OK but it would be nice for it to be scheduled.

I tried your suggestion, leaving it in an open terminal session, which returned 'job 3 at 2014-07-01 19:22'
but nothing happened at the appointed time. I would like it to open the iftop window, as the direct command does,
rather than send anything to a file.

Cheers

unSpawn · 07-02-2014, 02:45 PM

Quote:

Originally Posted by Sir Prised

I tried your suggestion, leaving it in an open terminal session, which returned 'job 3 at 2014-07-01 19:22' but nothing happened at the appointed time.

Well it did happen but you probably didn't kill the process afterwards as I suggested and you probably also didn't check your email after you killed the process?..

Quote:

Originally Posted by Sir Prised

I would like it to open the iftop window, as the direct command does, rather than send anything to a file.

Oh well. I won't bore you with details then but point you to 'man screen' as you need something to be able to "take over" your console even if you're not logged in and have it run 'iftop' for you.

Sir Prised · 07-02-2014, 02:58 PM

I have to say that it sounds as if you're answering the question you wish I'd ask?

i.e. I'm not looking at an email I never wanted in the first place !

Perhaps what I did ask isn't possible but hey ho, I can carry on doing it manually.

ATB

unSpawn · 07-03-2014, 01:43 AM

Quote:

Originally Posted by Sir Prised

I have to say that it sounds as if you're answering the question you wish I'd ask?
i.e. I'm not looking at an email I never wanted in the first place !

That's an odd way to phrase things.
I just explained how testing that method works.
What you do with that is your choice.

Quote:

Originally Posted by Sir Prised

Perhaps what I did ask isn't possible but hey ho, I can carry on doing it manually.

I pointed out one method to achieve what you want.
So maybe there's some language barrier here?..