Re: What is the ping timeout and is it configurable?

From: Jared Mauch (
Date: Tue Oct 09 2001 - 12:05:01 EDT

On Tue, Oct 09, 2001 at 09:54:12AM +0000, Simon White wrote:
> I have been looking through the source code but since I know very little
> C I have been unable to tell much more than the general structure.
> What I want to know is where the timeout for ping responses is defined.
> I can see the loops and stuff but don't see any particular way to gauge
> the timeout.
> Also, the equipment I am pinging cannot all be NTP synchronised; is
> there any allowance for replies coming back timestamped a couple minutes
> either way from the original ICMP echo packet send? Or is this
> irrelevant?

        This is not relevant. We do not encode the timestamp in our
echo-request packet or look at any timestamp inserted in the echo-reply

> Why am I asking?
> Because I get frequent "host down" messages only to have them back up 2
> minutes later, and I suspect that it is just ICMP replies taking over
> 500ms to get back, perhaps.

        The system currently sends 7 icmp echo-request packets

        it waits 1-2 seconds for a response before sending the next.

        if all 7 are missed, then it declares the host as down/unpingable.

        is your system running FreeBSD? I've seen some odd behaviour of
those hosts.

        - Jared

Jared Mauch  | pgp key available via finger from
clue++;      |  My statements are only mine.

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