On the Wed, Mar 26, 2008 at 02:42:36PM +0100, Tonnerre Lombard blubbered: Hoi.
> 1. it is highly unlikely that these stupid wannabe SPAM filters get the > response containing so many PTR records right. It is most likely > that either the software blows up or that it only ever considers the > entry it receives first. Most mailservers just check if there is a PTR record at all and if there is none, reject the mail with a 5xx DSN. > (Most likely the software blowing up will not even be remarked but > instead the mail will be rejected silently.) Clever spamfilters will just add another score point to the spam score and not just pass or discard a mail based on a single criteria. > > Under the line, it is likely not a DNS issue, but the inability by > > some mail or AS systems resolving lists. Suspect my servers will > > fail, too. Xaver, pls send private reply for a test from that system, > > anytime. > > It is also a DNS issue, depending on the number of results returned; > the size of a DNS/UDP response is limited to 1 UDP packet, which again > is limited in size. Not everyone uses DNS over TCP, and it is unlikely > to be adapted just because of such a stupid and useless SPAM filtering > measure. While Xari's Setup with tons of PTR records is plain stupid. Xari, you should have a read about MX records. =:-) But DNS uses UDP and TCP as I just checked. RFC 1035, Chapter 4.2 says: "The Internet supports name server access using TCP [RFC-793] on server port 53 (decimal) as well as datagram access using UDP [RFC-768] on UDP port 53 (decimal)." CU, Venty -- Wo Informationen fehlen, da entstehen Geruechte. _______________________________________________ swinog mailing list swinog@lists.swinog.ch http://lists.swinog.ch/cgi-bin/mailman/listinfo/swinog
