First, I am a CentOS 7 newbie. I am running an email server on CentOS 7, I am currently having issue with setting SMTPS up on postfix. BTW, imap over SSL on port 993 is working fine. Port 465 and SMTPS service were already added to firewall as well.
problem # 1: result of running telnet localhost 465
sudo telnet localhost 465 Trying ::1... Connected to localhost. Escape character is '^]'. Connection closed by foreign host.
problem # 2: result of running sudo openssl s_client -connect mail.server.com:465
CONNECTED(00000003) write:errno=104 --- no peer certificate available --- No client certificate CA names sent --- SSL handshake has read 0 bytes and written 247 bytes --- New, (NONE), Cipher is (NONE) Secure Renegotiation IS NOT supported Compression: NONE Expansion: NONE ---
Here is my config under /etc/postfix/main.cf
smtp_use_tls = yes smtp_tls_key_file = /etc/pki/tls/private/server.com.key smtp_tls_cert_file = /etc/pki/tls/certs/server.com.crt smtpd_tls_loglevel = 3 smtpd_tls_received_header = yes smtpd_tls_session_cache_timeout = 3600s tls_random_source = dev:/dev/urandom
And config under /etc/postfix/master.cf
smtp inet n - n - - smtpd #smtp inet n - n - 1 postscreen #smtpd pass - - n - - smtpd #dnsblog unix - - n - 0 dnsblog #tlsproxy unix - - n - 0 tlsproxy #submission inet n - n - - smtpd # -o syslog_name=postfix/submission # -o smtpd_tls_security_level=encrypt # -o smtpd_sasl_auth_enable=yes # -o smtpd_reject_unlisted_recipient=no # -o smtpd_client_restrictions=$mua_client_restrictions # -o smtpd_helo_restrictions=$mua_helo_restrictions # -o smtpd_sender_restrictions=$mua_sender_restrictions # -o smtpd_recipient_restrictions=permit_sasl_authenticated,reject # -o milter_macro_daemon_name=ORIGINATING smtps inet n - n - - smtpd # -o syslog_name=postfix/smtps -o smtpd_tls_wrappermode=yes -o smtpd_sasl_auth_enable=yes
I've tried many different methods to setup SMTPS on postfix online, but non of them worked. Could anyone help me? Thanks!