On 2018-05-30 17:35, Per Jessen wrote: > Jeroen Massar wrote: > >> On 2018-05-30 16:44, Per Jessen wrote: >>> According to RFC1034 and 2181, a PTR record using a CNAME is not >>> permitted. I believe this to still be correct, postfix certainly >>> doesn't work with a CNAME when it does a reverse lookup. >> >> Postfix certainly does as: >> >> $ dig +short 50.131.144.213.in-addr.arpa. ptr >> 50.63-28.131.144.213.in-addr.arpa. >> citadel.ch.unfix.org. >> >> would otherwise not work.... and that trick of CNAME'ing in-addr.arpa >> space is used a lot by ISPs to delegate space (as per the above >> example where init7 forwards them to my nameservers). >> >> There is also a nice RFC on that: >> https://www.ietf.org/rfc/rfc2317.txt > > Okay, thanks for clarifying that - I was wondering. I don't why my > postfixes come up with host name 'unknown'.
Where does postfix say 'unknown'? In the prepended "Received: from ..." header? in logs? Can be many reasons why it does not trust the originally provided data, especially as HELO/EHLO can be spoofed. Also depends on the resolver etc etc, many factors ;) Greets, Jeroen _______________________________________________ swinog mailing list [email protected] http://lists.swinog.ch/cgi-bin/mailman/listinfo/swinog
