Hi Robin,
> Hey guys,
>
> Actually when you get an NXDOMAIN reply you can just stop resolving that
> domain. Basically there are 2 types of "negative" replies in DNS:
>
> NODATA: basically this is when you don't get an error (NOERROR in dig),
> but not the actual data you are looking for. You might have gotten some
> CNAME data but no A or AAAA record (depending on what you wanted
> obviously). This means that the actual domain name does exist, but
> doesn't have data of the type you requested. The term NODATA is used in
> DNS RFC's but it doesn't actually have its own error code.
>
> NXDOMAIN: This is denoted by the NXDOMAIN error code. It means that
> either the domain you requested itself or the last target domain from a
> CNAME does not exist at all (IE no data whatsoever) and there also isn't
> a wildcard available that matches it. So if you asked for an A record,
> getting an NXDOMAIN means there also won't be an AAAA record.
>
> The above explanation is a bit of an over simplification cause there are
> also things like empty non-terminals which also don't have any data, but
> instead of an NXDOMAIN actually return a NODATA (in most cases, there
> are some authoritative servers that don't do it properly). But the end
> result is that you can pretty much say that when you get NXDOMAIN, there
> really is nothing there for you so you can just stop looking (at least
> at that the current server).
Thanks for clarifying, I didn't know about this. Good thing we didn't
implemented anything yet.
Baptiste, whats the current behavior when an empty response with
NOERROR is received?
Regards,
Lukas
