Sende bitte mal die Ausgabe von 'postconf -n' und nicht die von 'cat main.cf'. Und bitte auch ein vollständiges Log einer E-Mail von einem der vServer an die angegebene Adresse.
Ich hab die Config und den Logauszug von beiden gemacht.
# postconf -n (testhost.kervyn.de) alias_database = hash:/etc/aliases alias_maps = hash:/etc/aliases append_dot_mydomain = no biff = no compatibility_level = 2 inet_interfaces = loopback-only mailbox_size_limit = 0 message_size_limit = 512000000 mydestination = localhost myhostname = testhost.kervyn.de mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128 myorigin = $myhostname readme_directory = no recipient_delimiter = + relayhost = fra.mail.kervyn.de smtp_tls_CAfile = /etc/ssl/certs/ca-certificates.crt smtp_tls_loglevel = 1 smtp_tls_mandatory_protocols = !SSLv2,!SSLv3 smtp_tls_security_level = secure smtp_use_tls = yes smtpd_banner = $myhostname ESMTP $mail_name smtpd_relay_restrictions = check_recipient_access hash:/etc/postfix/host-specific-blacklisted, permit_mynetworks, defer_unauth_destination, reject_unknown_sender_domain
#grep 7106AA0132 /var/log/mail.log (testhost.kervyn.de) Mar 23 10:22:31 testhost postfix/pickup[31527]: 7106AA0132: uid=0 from=<root> Mar 23 10:22:31 testhost postfix/cleanup[31627]: 7106AA0132: message-id=20180323092231.7106AA0132@testhost.kervyn.de Mar 23 10:22:31 testhost postfix/qmgr[28977]: 7106AA0132: from=root@testhost.kervyn.de, size=319, nrcpt=1 (queue active) Mar 23 10:22:31 testhost postfix/smtp[31629]: 7106AA0132: to=bb@kervyn.de, relay=fra.mail.kervyn.de[10.211.100.5]:25, delay=0.13, delays=0.03/0.01/0.02/0.06, dsn=2.0.0, status=sent (250 2.0.0 Ok: queued as 7FF308115F) Mar 23 10:22:31 testhost postfix/qmgr[28977]: 7106AA0132: removed
# postconf -n (fra.mail.kervyn.de) alias_maps = hash:/etc/aliases append_dot_mydomain = no biff = no broken_sasl_auth_clients = yes config_directory = /etc/postfix inet_interfaces = all mailbox_size_limit = 0 message_size_limit = 512000000 milter_default_action = accept milter_protocol = 6 myhostname = relay03.mail.kervyn.de mynetworks = cidr:/etc/postfix/client_access myorigin = relay03.mail.kervyn.de non_smtpd_milters = inet:localhost:8891 readme_directory = no recipient_delimiter = + sender_canonical_classes = envelope_sender sender_canonical_maps = hash:/etc/postfix/sender_canonical sender_dependent_default_transport_maps = pcre:/etc/postfix/transport smtp_sasl_auth_enable = yes smtp_sasl_password_maps = hash:/etc/postfix/smtp_passwd smtp_sasl_security_options = noanonymous smtp_sasl_tls_security_options = noanonymous smtp_tls_CAfile = /etc/pki/tls/certs/ca-bundle.crt smtp_tls_loglevel = 1 smtp_tls_mandatory_protocols = !SSLv2,!SSLv3 smtp_tls_policy_maps = hash:/etc/postfix/tls_policy smtp_tls_security_level = may smtpd_banner = $myhostname ESMTP smtpd_data_restrictions = reject_unauth_pipelining smtpd_error_sleep_time = 1s smtpd_hard_error_limit = 20 smtpd_helo_required = yes smtpd_milters = inet:localhost:8891 smtpd_recipient_restrictions = permit_sasl_authenticated, permit_mynetworks, reject_non_fqdn_sender, reject_non_fqdn_recipient, reject_unknown_sender_domain, reject_unknown_recipient_domain, reject_rbl_client sbl.spamhaus.org, reject_rbl_client cbl.abuseat.org, reject_rbl_client dul.dnsbl.sorbs.net, reject_unauth_destination smtpd_sasl_auth_enable = yes smtpd_sasl_authenticated_header = no smtpd_sasl_local_domain = smtpd_sasl_security_options = noanonymous smtpd_sasl_type = cyrus smtpd_soft_error_limit = 10 smtpd_tls_CAfile = /etc/ssl/mail.kervyn.de.ca smtpd_tls_cert_file = /etc/ssl/mail.kervyn.de.crt smtpd_tls_dh1024_param_file = /etc/postfix/dhparams.pem smtpd_tls_key_file = /etc/ssl/mail.kervyn.de.key smtpd_tls_mandatory_exclude_ciphers = aNULL, eNULL, EXPORT, DES, RC4, MD5, PSK, aECDH, EDH-DSS-DES-CBC3-SHA, EDH-RSA-DES-CDC3-SHA, KRB5-DE5, CBC3-SHA smtpd_tls_received_header = yes smtpd_use_tls = yes transport_maps = pcre:/etc/postfix/transport hash:/etc/postfix/spamtraps virtual_alias_domains = hash:/etc/postfix/virtual, pcre:/etc/postfix/virtual_fallback virtual_alias_maps = hash:/etc/postfix/virtual, pcre:/etc/postfix/virtual_fallback
# grep 7FF308115F /var/log/maillog (fra.mail.kervyn.de) Mar 23 10:22:31 relay03 postfix/smtpd[7285]: 7FF308115F: client=testhost.kervyn.de[10.211.100.75] Mar 23 10:22:31 relay03 postfix/cleanup[7289]: 7FF308115F: message-id=20180323092231.7106AA0132@testhost.kervyn.de Mar 23 10:22:31 relay03 opendkim[411]: 7FF308115F: no signing table match for 'root@testhost.kervyn.de' Mar 23 10:22:31 relay03 postfix/qmgr[6631]: 7FF308115F: from=root@testhost.kervyn.de, size=662, nrcpt=1 (queue active) Mar 23 10:22:32 relay03 postfix/smtp[7290]: 7FF308115F: to=bb@kervyn.de, relay=ASPMX.L.GOOGLE.COM[74.125.140.27]:25, delay=0.53, delays=0.05/0.01/0.27/0.19, dsn=2.0.0, status=sent (250 2.0.0 OK 1521796950 y61si6570083wrc.386 - gsmtp) Mar 23 10:22:32 relay03 postfix/qmgr[6631]: 7FF308115F: removed