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. Peter
