Re: [lmap] A question about running actions in sequence

Fredrik Kers <> Wed, 17 May 2017 07:38 UTC

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From: Fredrik Kers <>
Date: Wed, 17 May 2017 09:35:16 +0200
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To: Juergen Schoenwaelder <>, Fredrik Kers <>,
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Subject: Re: [lmap] A question about running actions in sequence
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> Perhaps a somewhat kludgy workaround could be a schedule that does
> just the traceroute (with a duration set to cover the traceroutes)
> where the traceroute action feeds into another schedule (with a
> duration set to cover pings) that does the pings.

Yes, if you give the first Action with uncertain runtime enough margin to
finish, the result will be that they run in sequence. But probably with
some delay.

> /js
> PS: Personally, I find the concrete use case a bit surprising. If you
>     want to probe the path for a certain time, why not run traceroute
>     for a certain time; this causes roughly the same number of probe
>     packets and your measurement adjusts to any path changes during
>     the measurement itself. But perhaps you just picked this as an
>     example to illustrate the question.

Yes, it was just used as an example. You would face the same problem when
you combine any Action that runs until it's complete with an Action that
runs until it's stopped.

Thank you for your answer!


*Fredrik Kers* | CTO
*Netrounds* | Storgatan 7 | 972 38 LuleƄ | Sweden |