-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 postfix 2.? (How do I get the version?) linux 3.16.7-21-desktop x86_64
Our spam filter logs all traffic that flows through it; it is proxy-style filter rather than an add-on for a mail server. Recently I have noticed brief connections to the SMTP port from my local postfix installation that do nothing: It sends the "EHLO whatever" command, immediately followed by the "QUIT" command. Basically, Postfix is pinging the SMTP server to... do something? Verify the connection is still active? The ping occurs about every 5 minutes. There are four pings each time. Does anyone know what this behavior is about? Below are the SMTP-specific entries in the configuration files. - ----[ SMTP cf entries ]---- main.cf:relayhost = [smtp.sma.com] main.cf:smtpd_helo_required = no main.cf:smtpd_client_restrictions = main.cf:smtpd_helo_restrictions = main.cf:smtpd_sender_restrictions = hash:/etc/postfix/access main.cf:smtpd_recipient_restrictions = permit_mynetworks,reject_unauth_destination main.cf:smtp_sasl_auth_enable = yes main.cf:smtp_sasl_security_options = main.cf:smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd main.cf:smtpd_sasl_auth_enable = no main.cf:smtp_use_tls = yes main.cf:smtp_enforce_tls = yes main.cf:smtp_tls_CAfile = main.cf:smtp_tls_CApath = /etc/postfix/ssl/certs main.cf:smtp_tls_cert_file = main.cf:smtp_tls_key_file = main.cf:smtp_tls_session_cache_database = btree:/var/lib/postfix/smtpd_tls_session_cache main.cf:smtpd_use_tls = no main.cf:smtpd_tls_CAfile = main.cf:smtpd_tls_CApath = main.cf:smtpd_tls_cert_file = main.cf:smtpd_tls_key_file = main.cf:smtpd_tls_ask_ccert = no main.cf:smtpd_tls_received_header = no master.cf:smtp inet n - n - - smtpd master.cf:smtp unix - - n - - smtp master.cf:relay unix - - n - - smtp master.cf: -o smtp_fallback_relay= - ----[ end ]---- - -- James Moe moe dot james at sohnen-moe dot com 520.743.3936 -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iEUEARECAAYFAlVjfDgACgkQzTcr8Prq0ZNY0gCfQPQSCSk0yFLeSfCSz7whJAa1 2TEAl1FMed+ucwREuCJ9WbONHFxvmMU= =p+m1 -----END PGP SIGNATURE-----
