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