Thomas Preissler:
> Hello,
>
> I have now for some time Postfix listening on IPv6 on my server.
> When I send for example emails to [email protected] or
> [email protected] I receive them via IPv6, all is good.
> I also (very rarely though) receive "normal" emails via IPv6. So far so
> good.
>
> Basically when more and more email servers got IPv6 enabled, I sometimes
> saw
>
> Jun 14 19:20:02 dumbledor postfix/smtpd[1472]: NOQUEUE: reject: RCPT
> from unknown[2002:XXXX:XXX::XXXX:XXX]: 554 5.7.1 Service unavailable;
> Client host [2002:XXXX:XXX::4d49:4f1] blocked using bl.spamcop.net;
> from=<XXXXXXXXXXXXXXXXXXXXXXXXXXXX> to=<[email protected]>
> proto=ESMTP helo=<XXXXXXXXXXXXXXXXXXXXXXXXX>
>
> Long story short:
> * Some IPv6 addreses are DNSBL blocked, some or not. When they are
> blocked, they stay blocked and same for when they are not blocked
> (like the test IPv6 emailaddresses above).
> * They always get blocked by the first DNSBL entry - obviously.
> * Querying the DNSBL via their webinterface doesnt work for IPv6
> addresses, doing the same via the equivalent nslookup or dig command
> gives me NXDOMAIN.
> * No IPv6 firewall enabled, but I run a local only bind.
>
> Did anybody experience the same?
> The odd thing is, and I cannot get my head around that, is that it works
> for some, for others it never worked.
What is the IP address?
What NSLOOKUP query did you use?
Wietse
