Swiftmailer: unable to connect to TLS encryption

Question

I am trying to send emails through Symfony using Swiftmailer. On the production server, I get an error message:

[2016-08-20 11:59:37] app.ERROR: Exception occurred while flushing email queue: Unable to connect with TLS encryption [] [] 

This is what I have in my config.yml:

 swiftmailer: transport: smtp host: localhost username: [e-mail] password: testpw spool: { type: memory } encryption: tls port: 587 

Postfix is ​​my mail server, it was installed with Plesk.

This is my postfix main.cf:

 # See /usr/share/postfix/main.cf.dist for a commented, more complete version # Debian specific: Specifying a file name will cause the first # line of that file to be used as the name. The Debian default # is /etc/mailname. #myorigin = /etc/mailname smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu) biff = no # appending .domain is the MUA job. append_dot_mydomain = no # Uncomment the next line to generate "delayed mail" warnings #delay_warning_time = 4h readme_directory = no # TLS parameters smtpd_tls_cert_file = /etc/ssl/certs/smtpd.crt smtpd_tls_key_file = /etc/ssl/private/smtpd.key smtpd_use_tls = yes smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache # See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for # information on enabling SSL in the smtp client. smtpd_relay_restrictions = permit_mynetworks permit_sasl_authenticated defer_unauth_destination myhostname = derkvanderheide.nl alias_maps = hash:/etc/aliases, hash:/var/spool/postfix/plesk/aliases alias_database = hash:/etc/aliases mydestination = localdomain, localhost, localhost.localdomain, localhost relayhost = mynetworks = mailbox_command = procmail -a "$EXTENSION" mailbox_size_limit = 0 recipient_delimiter = + inet_interfaces = all inet_protocols = all virtual_mailbox_domains = $virtual_mailbox_maps, hash:/var/spool/postfix/plesk/virtual_domains virtual_alias_maps = $virtual_maps, hash:/var/spool/postfix/plesk/virtual virtual_mailbox_maps = , hash:/var/spool/postfix/plesk/vmailbox transport_maps = , hash:/var/spool/postfix/plesk/transport smtpd_tls_security_level = encrypt smtp_tls_security_level = may smtp_use_tls = yes smtpd_timeout = 3600s smtpd_proxy_timeout = 3600s disable_vrfy_command = yes smtpd_sender_restrictions = check_sender_access hash:/var/spool/postfix/plesk/blacklists, permit_sasl_authenticated smtpd_client_restrictions = permit_mynetworks, permit_sasl_authenticated smtp_send_xforward_command = yes smtpd_authorized_xforward_hosts = 127.0.0.0/8 [::1]/128 smtpd_sasl_auth_enable = yes smtpd_recipient_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination virtual_mailbox_base = /var/qmail/mailnames virtual_uid_maps = static:30 virtual_gid_maps = static:31 smtpd_milters = , inet:127.0.0.1:12768 sender_dependent_default_transport_maps = hash:/var/spool/postfix/plesk/sdd_transport_maps virtual_transport = plesk_virtual plesk_virtual_destination_recipient_limit = 1 mailman_destination_recipient_limit = 1 virtual_mailbox_limit = 0 smtpd_tls_mandatory_protocols = TLSv1 TLSv1.1 TLSv1.2 smtpd_tls_protocols = TLSv1 TLSv1.1 TLSv1.2 smtpd_tls_ciphers = medium smtpd_tls_mandatory_ciphers = medium tls_medium_cipherlist = HIGH:!aNULL:!MD5 message_size_limit = 10240000 smtpd_tls_auth_only = no smtp_tls_note_starttls_offer = yes smtpd_tls_CAfile = /etc/ssl/certs/cacert.pem smtpd_tls_loglevel = 1 smtpd_tls_received_header = yes smtpd_tls_session_cache_timeout = 3600s tls_random_source = dev:/dev/urandom 

This is the output from telnet:

 Trying 185.57.10.237... Connected to derkvanderheide.nl. Escape character is '^]'. 220 derkvanderheide.nl ESMTP Postfix (Ubuntu) ehlo localhost 250-derkvanderheide.nl 250-PIPELINING 250-SIZE 10240000 250-ETRN 250-STARTTLS 250-ENHANCEDSTATUSCODES 250-8BITMIME 250 DSN 

This is in my maillog:

 Aug 20 17:06:35 vps-248826-4222 postfix/smtpd[8592]: connect from vps-248826-4222.hosted.at.hostnet.nl[127.0.0.1] Aug 20 17:06:35 vps-248826-4222 postfix/smtpd[8592]: SSL_accept error from vps-248826-4222.hosted.at.hostnet.nl[127.0.0.1]: 0 Aug 20 17:06:35 vps-248826-4222 postfix/smtpd[8592]: warning: TLS library problem: error:14094418:SSL routines:SSL3_READ_BYTES:tlsv1 alert unknown ca:s3_pkt.c:1262:SSL alert number 48: Aug 20 17:06:35 vps-248826-4222 postfix/smtpd[8592]: lost connection after STARTTLS from vps-248826-4222.hosted.at.hostnet.nl[127.0.0.1] Aug 20 17:06:35 vps-248826-4222 postfix/smtpd[8592]: disconnect from vps-248826-4222.hosted.at.hostnet.nl[127.0.0.1] 

I have almost no clue what I'm doing, this is my first case with a mail server.

Answer 1

Try this solution:

 $opt['ssl']['verify_peer'] = FALSE; $opt['ssl']['verify_peer_name'] = FALSE; $this->get('swiftmailer.mailer.default.transport.real')->setStreamOptions($opt); 

which should be placed before: \Swift_Message::newInstance() in your controller