On 11.08.22 11:43, Nick Howitt wrote:
[root@server ~]# postconf -n | grep restrictions
Sometimes I see things like:
Aug 11 05:29:50 server postfix/smtpd[22642]: connect from
unknown[103.169.188.140]
Aug 9 15:53:47 server postfix/smtpd[16934]: connect from
unknown[162.240.216.231]
On 11/08/2022 11:54, Matus UHLAR - fantomas wrote:
this is the main diference between
reject_unknown_reverse_client_hostname and
reject_unknown_client_hostname.
- the first that you used doesn't check for fcrdns mapping and only
rejects IP addresses that have no reverse mapping, no matter if
the reverse hostname is random
On 11.08.22 12:56, Nick Howitt wrote:
Oh OK, so when it says "unknown" it only means that forward and
reverse DNS don't match? I was reading it that the reverse DNS didn't
exits.
postfix logs "unknown" when the reverse DNS does not exist or it resolves to
name that does not map back to the IP address.
I can't use reject_unknown_client_hostname as I know at least one
major ISP in the UK has their mailserver announcing a ???.local or
???.lan domain.
what's the difference if the reverse lookup points to something that does
not exist in domains .lan, .local and in .com, if those names don't resolve
back to that IP?
--
Matus UHLAR - fantomas, uh...@fantomas.sk ; http://www.fantomas.sk/
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Varovanie: na tuto adresu chcem NEDOSTAVAT akukolvek reklamnu postu.
Linux is like a teepee: no Windows, no Gates and an apache inside...
