IP address 2002:4d49:4f1::4d49:4f1 is not blocked here, neither in postscreen nor in smtpd:
postconf -n: postscreen_dnsbl_sites = bl.spamcop.net smtpd_client_restrictions = reject_rbl_client bl.spamcop.net logging: Jun 17 14:29:30 tail postfix/postscreen[14560]: CONNECT from [2002:4d49:4f1::4d49:4f1]:25 to [2002:4d49:4f1::4d49:4f1]:25 Jun 17 14:29:30 tail postfix/postscreen[14560]: PASS NEW [2002:4d49:4f1::4d49:4f1]:25 ... Jun 17 14:30:59 tail postfix/smtpd[14594]: connect from unknown[2002:4d49:4f1::4d49:4f1] Jun 17 14:31:23 tail postfix/smtpd[14594]: 3WFkXq5jt3znktg: client=unknown[2002:4d49:4f1::4d49:4f1] Jun 17 14:31:31 tail postfix/smtpd[14594]: disconnect from unknown[2002:4d49:4f1::4d49:4f1] This test uses new code to override client and server address and port information. Not having a lot of imagination I specified the same numbers for the client and server address and port. When I specify 127.0.0.2 as the client, it is blocked. Wietse