Hi, I'm getting this kind of error on my Mail Warn Log: Code: Sep 11 20:00:47 server postfix/smtps/smtpd[8967]: warning: TLS library problem: error:1417D0FC:SSL routines:tls_process_client_hello:unknown protocol:../ssl/statem/statem_srvr.c:938: Sep 11 20:00:48 server postfix/smtps/smtpd[8964]: warning: TLS library problem: error:140940F5:SSL routines:ssl3_read_bytes:unexpected record:../ssl/record/rec_layer_s3.c:1478: Sep 11 20:00:48 server postfix/smtps/smtpd[8964]: warning: TLS library problem: error:1417D18C:SSL routines:tls_process_client_hello:version too low:../ssl/statem/statem_srvr.c:974: Sep 11 20:00:49 server postfix/smtps/smtpd[8966]: warning: TLS library problem: error:140A1175:SSL routines:ssl_bytes_to_cipher_list:inappropriate fallback:../ssl/statem/statem_srvr.c:3310: Sep 11 20:00:50 server postfix/smtps/smtpd[8976]: warning: TLS library problem: error:1417A0C1:SSL routines:tls_post_process_client_hello:no shared cipher:../ssl/statem/statem_srvr.c:1404: Sep 11 20:00:50 server postfix/smtps/smtpd[8972]: warning: TLS library problem: error:1417A0C1:SSL routines:tls_post_process_client_hello:no shared cipher:../ssl/statem/statem_srvr.c:1404: Sep 11 20:00:51 server postfix/smtps/smtpd[8970]: warning: TLS library problem: error:1417A0C1:SSL routines:tls_post_process_client_hello:no shared cipher:../ssl/statem/statem_srvr.c:1404: Sep 11 20:00:51 server postfix/smtps/smtpd[8972]: warning: TLS library problem: error:1417A0C1:SSL routines:tls_post_process_client_hello:no shared cipher:../ssl/statem/statem_srvr.c:1404: Sep 11 20:00:51 server postfix/smtps/smtpd[8975]: warning: TLS library problem: error:1417A0C1:SSL routines:tls_post_process_client_hello:no shared cipher:../ssl/statem/statem_srvr.c:1404: Sep 11 20:00:51 server postfix/smtps/smtpd[8967]: warning: TLS library problem: error:1417A0C1:SSL routines:tls_post_process_client_hello:no shared cipher:../ssl/statem/statem_srvr.c:1404: Sep 11 20:00:51 server postfix/smtps/smtpd[8975]: warning: TLS library problem: error:1417A0C1:SSL routines:tls_post_process_client_hello:no shared cipher:../ssl/statem/statem_srvr.c:1404: Sep 11 20:00:52 server postfix/smtps/smtpd[8969]: warning: TLS library problem: error:1417A0C1:SSL routines:tls_post_process_client_hello:no shared cipher:../ssl/statem/statem_srvr.c:1404: Sep 11 20:00:53 server postfix/smtps/smtpd[8970]: warning: TLS library problem: error:1417A0C1:SSL routines:tls_post_process_client_hello:no shared cipher:../ssl/statem/statem_srvr.c:1404: Sep 11 20:00:54 server postfix/smtps/smtpd[8970]: warning: TLS library problem: error:1417A0C1:SSL routines:tls_post_process_client_hello:no shared cipher:../ssl/statem/statem_srvr.c:1404: Sep 11 20:00:54 server postfix/smtps/smtpd[8966]: warning: TLS library problem: error:1417A0C1:SSL routines:tls_post_process_client_hello:no shared cipher:../ssl/statem/statem_srvr.c:1404: Sep 11 20:00:54 server postfix/smtps/smtpd[8974]: warning: TLS library problem: error:1417A0C1:SSL routines:tls_post_process_client_hello:no shared cipher:../ssl/statem/statem_srvr.c:1404: Sep 11 21:01:44 server postfix/smtpd[8292]: warning: hwsrv-315220.hostwindsdns.com[23.254.202.137]: SASL login authentication failed: UGFzc3dvcmQ6 Sep 11 21:07:04 server postfix/smtpd[12962]: warning: hwsrv-315226.hostwindsdns.com[23.254.202.123]: SASL login authentication failed: UGFzc3dvcmQ6 Sep 11 22:54:25 server postfix/smtpd[18327]: warning: hwsrv-315220.hostwindsdns.com[23.254.202.137]: SASL login authentication failed: UGFzc3dvcmQ6 Sep 11 23:00:54 server postfix/smtpd[18327]: warning: hwsrv-315220.hostwindsdns.com[23.254.202.137]: SASL login authentication failed: UGFzc3dvcmQ6 Sep 12 11:30:42 server postfix/smtpd[30269]: warning: hostname cl46074p.m.maintenis.com does not resolve to address 45.64.1.81: Name or service not known Sep 12 17:00:02 server postfix/smtpd[18039]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 12 17:00:02 server postfix/smtpd[18039]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 12 17:00:02 server postfix/smtpd[18039]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 12 17:00:02 server postfix/smtpd[18039]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 12 17:00:02 server postfix/smtpd[18039]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 12 17:00:02 server postfix/smtpd[18039]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 12 17:00:02 server postfix/smtpd[18039]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 12 17:00:02 server postfix/smtpd[18039]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 12 17:00:02 server postfix/smtpd[18039]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 12 17:00:02 server postfix/smtpd[18039]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 12 20:31:56 server postfix/smtpd[31107]: warning: hostname zg-0906c-28.stretchoid.com does not resolve to address 107.170.204.100: Name or service not known Sep 13 06:30:34 server postfix/smtps/smtpd[625]: warning: hostname zg-0906b-74.stretchoid.com does not resolve to address 107.170.234.22: Name or service not known Sep 13 17:00:01 server postfix/smtpd[10634]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 13 17:00:01 server postfix/smtpd[10634]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 13 17:00:01 server postfix/smtpd[10634]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 13 17:00:01 server postfix/smtpd[10634]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 13 17:00:01 server postfix/smtpd[10634]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 13 17:00:01 server postfix/smtpd[10634]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 13 17:00:01 server postfix/smtpd[10634]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 13 17:00:01 server postfix/smtpd[10634]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 13 17:00:01 server postfix/smtpd[10634]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 13 17:00:01 server postfix/smtpd[10634]: warning: table "mysql:/etc/postfix/mysql-virtual_client.cf": empty query string -- ignored Sep 14 02:56:11 server postfix/smtpd[10942]: warning: unknown[185.234.219.54]: SASL LOGIN authentication failed: UGFzc3dvcmQ6 Sep 14 04:38:04 server postfix/smtpd[17616]: warning: hostname no-reverse-dns-configured.com does not resolve to address 89.248.167.159 Sep 14 04:38:08 server postfix/smtpd[17616]: warning: unknown[89.248.167.159]: SASL LOGIN authentication failed: UGFzc3dvcmQ6 is there anything i can do to fix this warn error?
It might be that someone tried to connect with an SSL protocol that's too old or someone tested your server for vulnerable protocols. If the mail system is working fine besides having these errors in the log, I would just ignore the error.
