logging sometimes fails
David W. Hankins
David_Hankins at isc.org
Wed Aug 23 22:54:35 UTC 2006
On Wed, Aug 23, 2006 at 04:00:05PM -0400, Randy Grimshaw wrote:
> As it is sometimes useful for debugging, I have been logging the dhcp
> fingerprint of the systems on our network.
> But have noticed that some systems such as Macintosh OSX are curiously
> absent... the log() seems to be failing.
>
> on commit {
> log(info,
> concat("Fingerprint:\t",
> binary-to-ascii(16, 8, ":", substring(hardware, 1, 6)),
> "\t",
> binary-to-ascii(10, 8, "-", option dhcp-parameter-request-list),
> "\t",
> option vendor-class-identifier
> )
> );
> }
>
> I woudn't post this to the list yet because such a failure could reveal
> other exposures.... but I am curious.
> have you seen anything like this elsewhere?
concat() returns a null value if any of its arguments are null (not
present, or of zero length).
I suspect the vendor-class-identifier is not present on the clients
that are not logging in your case.
Consider:
pick-first-value(option vendor-class-identifier, "<none>")
--
ISC Training! October 16-20, 2006, in the San Francisco Bay Area,
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--
David W. Hankins "If you don't do it right the first time,
Software Engineer you'll just have to do it again."
Internet Systems Consortium, Inc. -- Jack T. Hankins
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