[smokeping-users] Satellite link - Packet Loss error

[Tobias Oetiker]

Hi Chris,

you can also just set the timeout property in the smokeping config
file for the FPing probe. Note that the timeout is configured in
seconds there !


The problem with the timeout is that if you set it to 10s and you
do not actally have links whith this propperty, then every lost
packet will cause fping to wait for 10 seconds which can hurt
performance ...

cheers
tobi



Today Chris Wilson wrote:

> Hi Adrian,
>
> On Wed, 10 Oct 2007, Adrian Minta wrote:
>
> > fping -aef myhostlist.txt works but repeated pings to one host fail if the
> > rtr > 580ms.
> >
> > fping -C 5 -q 10.10.10.33
> > 10.10.10.33 : 552.39 563.67 548.83 560.51 -
> >
> > So for fping the Packet Loss is 1/5 = 20%
> > I am using  fping (2.4b2-to-ipv6-14) debian default.
>
> We see this as well. The way smokeping uses fping by default, it does not
> wait long enough for the last ping to come in. We have to hack smokeping
> by hand to do it. I edit lib/Smokeping/probes/FPing.pm and change the @cmd
> lines as follows:
>
>     my @cmd = (
>                     $self->binary,
>                     '-C', $self->pings, '-q','-B1','-r1','-t10000',
>                     @params,
>                     @{$self->addresses});
>
> I think -t10000 is the important one. It sets the timeout to 10 seconds
> (default is 500ms).
>
> Cheers, Chris.
>

-- 
Tobi Oetiker, OETIKER+PARTNER AG, Aarweg 15 CH-4600 Olten
http://it.oetiker.ch tobi at oetiker.ch ++41 62 213 9902