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