Peter:
[ Charset windows-1252 converted... ]
> On 07/06/16 12:23, Wietse Venema wrote:
> >> dnsblog(8) states, "Otherwise it replies with the query arguments plus
> >> an empty address list and the reply TTL (-1 if unavailable)." It is
> >> unclear that this references the negative cache TTL as returned by the
> >> SOA record included in an NXDOMAIN response.
> >>
> >> I had to look at the dnsblog.c source code for this to become clear.
> >
> > The -1 is not related to caching for negative responses.
> >
> > The -1 means there was no reply, or the reply contained no TTL
> > information (which happens with an NXDOMAIN response without authority
> > records).
>
> Right, I understand that. I was referring to the part just before that,
> the "Otherwise" appears to refer (at least partially) to a negative
> response, but there is nothing that actually states that a negative
> response returns the negative cache TTL from the SOA header. As I said,
> I had to look to the source code to confirm that this is actually what
> happens.
The text says:
If the IP address is listed [..] the dnsblog(8) server [..]
replies with [..].
This describes a "found" response.
Otherwise it replies with the query arguments plus an empty
address list and the reply TTL (-1 if unavailable).
"otherwise" means that the IP address is not listed, or that no
reply was received.
I have changed the text to:
Otherwise it replies with the query arguments plus an empty
address list and the reply TTL. The reply TTL is -1 if no
reply is received, or if the reply contains no TTL information).
Wietse
