postconf -n

broken_sasl_auth_clients = yes
command_directory = /usr/local/sbin
config_directory = /usr/local/etc/postfix
daemon_directory = /usr/local/libexec/postfix
data_directory = /var/db/postfix
debug_peer_level = 2
html_directory = /usr/local/share/doc/postfix
mail_owner = postfix
mailq_path = /usr/local/bin/mailq
manpage_directory = /usr/local/man
mydestination = localhost.$mydomain, localhost
mydomain = domain.com
myhostname = host.domain.com
mynetworks_style = host
newaliases_path = /usr/local/bin/newaliases
proxy_read_maps = $local_recipient_maps $mydestination $virtual_alias_maps  $virtual_alias_domains $virtual_mailbox_maps $virtual_mailbox_domains  $relay_recipient_maps $relay_domains $canonical_maps $sender_canonical_maps  $recipient_canonical_maps $relocated_maps $transport_maps $mynetworks  $virtual_mailbox_limit_maps
queue_directory = /var/spool/postfix
readme_directory = /usr/local/share/doc/postfix
relay_domains = proxy:mysql:/usr/local/etc/postfix/mysql_relay_domains_maps.cf
sample_directory = /usr/local/etc/postfix
sendmail_path = /usr/local/sbin/sendmail
setgid_group = maildrop
smtp_tls_note_starttls_offer = yes
smtp_use_tls = yes
smtpd_recipient_restrictions = permit_mynetworks,  permit_sasl_authenticated,  reject_non_fqdn_hostname,  reject_non_fqdn_sender,  reject_non_fqdn_recipient,  reject_unauth_destination,  reject_unauth_pipelining,  reject_invalid_hostname,  reject_rbl_client list.dsbl.org,  reject_rbl_client bl.spamcop.net,  reject_rbl_client sbl-xbl.spamhaus.org
smtpd_sasl_auth_enable = yes
smtpd_sasl_authenticated_header = yes
smtpd_sasl_local_domain = $myhostname
smtpd_sasl_path = private/auth
smtpd_sasl_security_options = noanonymous
smtpd_sasl_type = dovecot
smtpd_sender_restrictions = permit_sasl_authenticated, permit_mynetworks
smtpd_tls_CAfile = /etc/ssl/postfix/smtpd.pem
smtpd_tls_cert_file = /etc/ssl/postfix/smtpd.pem
smtpd_tls_key_file = /etc/ssl/postfix/smtpd.pem
smtpd_tls_loglevel = 0
smtpd_tls_received_header = yes
smtpd_tls_session_cache_timeout = 3600s
smtpd_use_tls = yes
soft_bounce = no
tls_random_source = dev:/dev/urandom
transport_maps = hash:/usr/local/etc/postfix/transport
unknown_local_recipient_reject_code = 550
virtual_alias_maps = proxy:mysql:/usr/local/etc/postfix/mysql_virtual_alias_maps.cf
virtual_gid_maps = static:125
virtual_mailbox_base = /usr/local/virtual
virtual_mailbox_domains = proxy:mysql:/usr/local/etc/postfix/mysql_virtual_domains_maps.cf
virtual_mailbox_limit = 51200000
virtual_mailbox_limit_maps = proxy:mysql:/usr/local/etc/postfix/mysql_virtual_mailbox_limit_maps.cf
virtual_mailbox_limit_override = yes
virtual_mailbox_maps = proxy:mysql:/usr/local/etc/postfix/mysql_virtual_mailbox_maps.cf
virtual_maildir_limit_message = Sorry, this user has overdrawn their diskspace quota. Please try again later.
virtual_minimum_uid = 125
virtual_overquota_bounce = yes
virtual_transport = virtual
virtual_uid_maps = static:125


/var/log/mail logs:

Jun 11 09:24:01 milo postfix/master[71953]: warning: process /usr/local/libexec/postfix/proxymap pid 72219 exit status 1
Jun 11 09:24:01 milo postfix/master[71953]: warning: /usr/local/libexec/postfix/proxymap: bad command startup -- throttling
Jun 11 09:25:01 milo postfix/proxymap[73950]: fatal: open /usr/local/etc/postfix/mysql_relay_domains_maps.cf: Permission denied
Jun 11 09:25:02 milo postfix/qmgr[72151]: warning: private/proxymap socket: service dict_proxy_open: Unknown error: 0
Jun 11 09:25:02 milo postfix/master[71953]: warning: process /usr/local/libexec/postfix/proxymap pid 73950 exit status 1
Jun 11 09:25:02 milo postfix/master[71953]: warning: /usr/local/libexec/postfix/proxymap: bad command startup -- throttling
Jun 11 09:26:02 milo postfix/proxymap[74275]: fatal: open /usr/local/etc/postfix/mysql_relay_domains_maps.cf: Permission denied
Jun 11 09:26:03 milo postfix/qmgr[72151]: warning: private/proxymap socket: service dict_proxy_open: Unknown error: 0
Jun 11 09:26:03 milo postfix/master[71953]: warning: process /usr/local/libexec/postfix/proxymap pid 74275 exit status 1
Jun 11 09:26:03 milo postfix/master[71953]: warning: /usr/local/libexec/postfix/proxymap: bad command startup -- throttling
Jun 11 09:27:03 milo postfix/proxymap[74332]: fatal: open /usr/local/etc/postfix/mysql_relay_domains_maps.cf: Permission denied
Jun 11 09:27:04 milo postfix/qmgr[72151]: warning: private/proxymap socket: service dict_proxy_open: Unknown error: 0
Jun 11 09:27:04 milo postfix/master[71953]: warning: process /usr/local/libexec/postfix/proxymap pid 74332 exit status 1
Jun 11 09:27:04 milo postfix/master[71953]: warning: /usr/local/libexec/postfix/proxymap: bad command startup -- throttling
Jun 11 09:28:04 milo postfix/proxymap[74663]: fatal: open /usr/local/etc/postfix/mysql_relay_domains_maps.cf: Permission denied
Jun 11 09:28:05 milo postfix/qmgr[72151]: warning: private/proxymap socket: service dict_proxy_open: Unknown error: 0
Jun 11 09:28:05 milo postfix/master[71953]: warning: process /usr/local/libexec/postfix/proxymap pid 74663 exit status 1
Jun 11 09:28:05 milo postfix/master[71953]: warning: /usr/local/libexec/postfix/proxymap: bad command startup -- throttling
Jun 11 09:29:05 milo postfix/proxymap[74985]: fatal: open /usr/local/etc/postfix/mysql_relay_domains_maps.cf: Permission denied
Jun 11 09:29:06 milo postfix/qmgr[72151]: warning: private/proxymap socket: service dict_proxy_open: Unknown error: 0
Jun 11 09:29:06 milo postfix/master[71953]: warning: process /usr/local/libexec/postfix/proxymap pid 74985 exit status 1
Jun 11 09:29:06 milo postfix/master[71953]: warning: /usr/local/libexec/postfix/proxymap: bad command startup -- throttling
Jun 11 09:30:06 milo postfix/proxymap[76387]: fatal: open /usr/local/etc/postfix/mysql_relay_domains_maps.cf: Permission denied
Jun 11 09:30:07 milo postfix/qmgr[72151]: warning: private/proxymap socket: service dict_proxy_open: Unknown error: 0
Jun 11 09:30:07 milo postfix/master[71953]: warning: process /usr/local/libexec/postfix/proxymap pid 76387 exit status 1
Jun 11 09:30:07 milo postfix/master[71953]: warning: /usr/local/libexec/postfix/proxymap: bad command startup -- throttling
Jun 11 09:31:08 milo postfix/proxymap[76646]: fatal: open /usr/local/etc/postfix/mysql_relay_domains_maps.cf: Permission denied
Jun 11 09:31:09 milo postfix/qmgr[72151]: warning: private/proxymap socket: service dict_proxy_open: Unknown error: 0
Jun 11 09:31:09 milo postfix/master[71953]: warning: process /usr/local/libexec/postfix/proxymap pid 76646 exit status 1
Jun 11 09:31:09 milo postfix/master[71953]: warning: /usr/local/libexec/postfix/proxymap: bad command startup -- throttling
Jun 11 09:32:09 milo postfix/proxymap[76655]: fatal: open /usr/local/etc/postfix/mysql_relay_domains_maps.cf: Permission denied
Jun 11 09:32:10 milo postfix/qmgr[72151]: warning: private/proxymap socket: service dict_proxy_open: Unknown error: 0
Jun 11 09:32:10 milo postfix/master[71953]: warning: process /usr/local/libexec/postfix/proxymap pid 76655 exit status 1
Jun 11 09:32:10 milo postfix/master[71953]: warning: /usr/local/libexec/postfix/proxymap: bad command startup -- throttling
Jun 11 09:33:10 milo postfix/proxymap[82787]: fatal: open /usr/local/etc/postfix/mysql_relay_domains_maps.cf: Permission denied
Jun 11 09:33:11 milo postfix/qmgr[72151]: warning: private/proxymap socket: service dict_proxy_open: Unknown error: 0
Jun 11 09:33:11 milo postfix/master[71953]: warning: process /usr/local/libexec/postfix/proxymap pid 82787 exit status 1
Jun 11 09:33:11 milo postfix/master[71953]: warning: /usr/local/libexec/postfix/proxymap: bad command startup -- throttling
Jun 11 09:34:11 milo postfix/proxymap[82994]: fatal: open /usr/local/etc/postfix/mysql_relay_domains_maps.cf: Permission denied
Jun 11 09:34:12 milo postfix/qmgr[72151]: warning: private/proxymap socket: service dict_proxy_open: Unknown error: 0
Jun 11 09:34:12 milo postfix/master[71953]: warning: process /usr/local/libexec/postfix/proxymap pid 82994 exit status 1
Jun 11 09:34:12 milo postfix/master[71953]: warning: /usr/local/libexec/postfix/proxymap: bad command startup -- throttling
Jun 11 09:35:12 milo postfix/proxymap[84188]: fatal: open /usr/local/etc/postfix/mysql_relay_domains_maps.cf: Permission denied
Jun 11 09:35:13 milo postfix/qmgr[72151]: warning: private/proxymap socket: service dict_proxy_open: Unknown error: 0
Jun 11 09:35:13 milo postfix/master[71953]: warning: process /usr/local/libexec/postfix/proxymap pid 84188 exit status 1
Jun 11 09:35:13 milo postfix/master[71953]: warning: /usr/local/libexec/postfix/proxymap: bad command startup -- throttling