On Mon, Apr 25, 2022 at 03:26:52PM -0700, Greg Earle wrote: > All of the sending hostnames are of the form > > www-data@vNNN-NNN-NNN-NNN.*.static.cnode.io
That's not a hostname, it is an email address, and not clear whether the envelope sender or the "From:" message header. > For example, here are some examples of the sending IPs from the last few > months: > > v163-44-192-240.a001.g.han1.static.cnode.io > v163-44-207-233.a006.g.han1.static.cnode.io > v150-95-115-46.a017.g.han1.static.cnode.io > v150-95-115-69.a017.g.han1.static.cnode.io > v163-44-155-225.a010.g.sin1.static.cnode.io > v160-251-100-196.wbeh.static.cnode.io Presumably SMTP client reverse names (PTR records), but these are again not necessarily the same as the EHLO names, > [root@isolar tmp]# cat /etc/postfix/helo.regexp > /v[0-9]+-[0-9]+-[0-9]+-[0-9]+[.-@]/ REJECT This pattern is nor properly anchored, possibly matching lots of other sources. A more conservative pattern would be: /^v[0-9]+-[0-9]+-[0-9]+-[0-9]+[.].*[.]static[.]cnode[.]io$/ REJECT > yet it didn't work - I got a spam from this IP today. What am I doing > wrong? Posting output of "grep", rather than full "postconf -nf" and "postconf -Mf" results. > (I'd be happy if I could just block *.static.cnode.io from connecting, > but I tried doing that in /etc/postfix/client_access and it didn't work > there, either.) The correct lookup keys would be: static.cnode.io .static.cnode.io See also: http://www.postfix.org/postconf.5.html#parent_domain_matches_subdomains http://www.postfix.org/access.5.html -- Viktor.