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Apr 21 11:46:18 amber postfix/smtpd[20823]: fatal: open database /etc/mail/aliases.db: No such file or directory
Apr 21 11:46:19 amber postfix/master[20655]: warning: process /usr/lib64/postfix/smtpd pid 20823 exit status 1
Apr 21 11:46:19 amber postfix/master[20655]: warning: /usr/lib64/postfix/smtpd: bad command startup -- throttling
Apr 21 11:46:22 amber postfix/local[20824]: fatal: open database /etc/mail/aliases.db: No such file or directory
Apr 21 11:46:23 amber postfix/master[20655]: warning: process /usr/lib64/postfix/local pid 20824 exit status 1
Apr 21 11:46:23 amber postfix/master[20655]: warning: /usr/lib64/postfix/local: bad command startup -- throttling

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# --------------- local settings ------------------
myhostname = myserver.example.com
inet_interfaces = localhost, $myhostname
mynetworks = $config_directory/mynetworks
mydestination = localhost.$mydomain, localhost, $myhostname
#uncomment if you need relay_domains... do not list domains in both relay and virtual
#relay_domains = proxy:mysql:$config_directory/mysql_relay_domains_maps.cf
# ---------------------- VIRTUAL DOMAINS START ----------------------
virtual_mailbox_domains = proxy:mysql:$config_directory/mysql_virtual_domains_maps.cf
virtual_mailbox_base = /var/vmail
virtual_mailbox_maps = proxy:mysql:$config_directory/mysql_virtual_mailbox_maps.cf
virtual_alias_maps = proxy:mysql:$config_directory/mysql_virtual_alias_maps.cf
virtual_minimum_uid = 101
virtual_uid_maps = static:101
virtual_gid_maps = static:12
virtual_transport = dovecot
dovecot_destination_recipient_limit = 1
# ---------------------- VIRTUAL DOMAINS END ----------------------
# ---------------------- SASL PART START ----------------------
smtpd_sasl_auth_enable = yes
#smtpd_sasl_local_domain = $myhostname
smtpd_sasl_exceptions_networks = $mynetworks
smtpd_sasl_security_options = noanonymous
broken_sasl_auth_clients = yes
smtpd_sasl_type = dovecot
# Can be an absolute path, or relative to $queue_directory
smtpd_sasl_path = private/auth
# ---------------------- SASL PART END ----------------------
# ---------------------- TLS PART START ----------------------
smtp_tls_CAfile = /etc/pki/tls/certs/cert.pem
smtp_tls_cert_file = /etc/pki/tls/certs/myserver.example.com.crt
smtp_tls_key_file = /etc/pki/tls/private/myserver.example.com.key
#Postfix 2.5 or greater must use:
#smtp_tls_session_cache_database = btree:$data_directory/smtp_tls_session_cache
smtp_tls_session_cache_database = btree:/var/spool/postfix/smtp_tls_session_cache
smtp_tls_security_level = may
smtpd_tls_CAfile = /etc/pki/tls/certs/cert.pem
smtpd_tls_cert_file = /etc/pki/tls/certs/myserver.example.com.crt
smtpd_tls_key_file = /etc/pki/tls/private/myserver.example.com.key
#Postfix 2.5 or greater must use:
#smtpd_tls_session_cache_database = btree:$data_directory/smtpd_tls_session_cache
smtpd_tls_session_cache_database = btree:/var/spool/postfix/smtpd_tls_session_cache
smtpd_tls_dh1024_param_file = $config_directory/dh_1024.pem
smtpd_tls_dh512_param_file = $config_directory/dh_512.pem
smtpd_tls_security_level = may
smtpd_tls_received_header = yes
smtpd_tls_ask_ccert = yes
smtpd_tls_loglevel = 1
tls_random_source = dev:/dev/urandom
# ---------------------- TLS PART END ----------------------
smtpd_helo_required = yes
disable_vrfy_command = yes
non_fqdn_reject_code = 450
invalid_hostname_reject_code = 450
maps_rbl_reject_code = 450
#unverified_sender_reject_code = 550
#header_checks = pcre:$config_directory/header_checks
#body_checks = pcre:$config_directory/body_checks
#warning: the restrictions reject_unknown_(sender|recipient)_domain
#will trigger if your DNS becomes unavailable
smtpd_recipient_restrictions =
permit_mynetworks
permit_sasl_authenticated
reject_unauth_destination
reject_invalid_helo_hostname
warn_if_reject reject_non_fqdn_helo_hostname
warn_if_reject reject_unknown_helo_hostname
warn_if_reject reject_unknown_client
reject_non_fqdn_sender
reject_non_fqdn_recipient
reject_unknown_sender_domain
reject_unknown_recipient_domain
reject_rbl_client zen.spamhaus.org
reject_rbl_client bl.spamcop.net
reject_rbl_client dnsbl.sorbs.net=127.0.0.2
reject_rbl_client dnsbl.sorbs.net=127.0.0.3
reject_rbl_client dnsbl.sorbs.net=127.0.0.4
reject_rbl_client dnsbl.sorbs.net=127.0.0.5
reject_rbl_client dnsbl.sorbs.net=127.0.0.7
reject_rbl_client dnsbl.sorbs.net=127.0.0.9
reject_rbl_client dnsbl.sorbs.net=127.0.0.11
reject_rbl_client dnsbl.sorbs.net=127.0.0.12
warn_if_reject reject_rhsbl_sender dsn.rfc-ignorant.org
warn_if_reject reject_rhsbl_sender abuse.rfc-ignorant.org
warn_if_reject reject_rhsbl_sender whois.rfc-ignorant.org
warn_if_reject reject_rhsbl_sender bogusmx.rfc-ignorant.org
warn_if_reject reject_rhsbl_sender postmaster.rfc-ignorant.org
permit
smtpd_data_restrictions =
reject_unauth_pipelining,
reject_multi_recipient_bounce,
permit