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From: pacho baratta <pachox@evolinux.it>
To: linux-admin@vger.kernel.org
Subject: Re: weird script behaviour
Date: 23 May 2003 16:26:55 +0200	[thread overview]
Message-ID: <1053700015.1246.39.camel@alice> (raw)

Il ven, 2003-05-23 alle 14:48, urgrue ha scritto:
> i have script that runs ok from the prompt but doesnt run ok at all 
> from cron (yes we've all seen this before, but this time its weirder 
> than usually).
> i even tried running it with env -i , but i cant reproduce the problem
> at the shell - it only appears when started from cron.
> the problem also does NOT appear when started with "at".
> i snipped the script down to a bare test minimum and am still able to 
> reproduce the error, here it is:
> 
> #!/bin/bash
> 
> while true
> do
> sleep 1
> echo "start" | logger
> ping -n -c 1 -w 3 10.155.11.37 && continue
> echo "we didnt continue..... | logger
> done
> 
> point is to spot if a ping doesnt go.
> run from the prompt, it works fine - it pings every second and i never
> get to the "we didnt continue" part.
> run from cron, it may or may not run ok for a little while (a minute
or 
> so), but then it starts to repeatedly reach the "we didnt continue" 
> part - and itll keep hitting that part over and over again until i 
> intervene.
> with a little extra checking, i found out that the ping isn't
returning 
> zero (as it does from the shell), but its returning 141! where does 
> this come from? why does it only start appearing after a minute or so?

the script is not good here's the prob.

u say 
echo "we didnt continue..... | logger

without an "if...then" it's always true, so u always do echo "we
didn't..."

i'd better wrie so:

#!/bin/sh
while true
do
sleep 1
echo "start" | logger
if ping -n -c 1 -w 3 10.155.11.37
then echo "ping works and host is up, man!!" | logger
else echo "ping what?? is network up? is that host up??" | logger
fi
done

regards, pacho



-- 
pacho baratta			IT Consultant
tel. +39 347 078.51.31		www.evolinux.it
mail: pachox@evolinux.it


             reply	other threads:[~2003-05-23 14:26 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2003-05-23 14:26 pacho baratta [this message]
  -- strict thread matches above, loose matches on Subject: below --
2003-05-23 12:48 weird script behaviour urgrue
2003-05-23 13:34 ` Jamie Harris

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