postfix mail queue and backscatter

Discussion in 'Installation/Configuration' started by lifeisboost, Oct 18, 2011.

  1. lifeisboost

    lifeisboost New Member

    Well one of my servers got hit hard today in a couple of hours we have gotten over 30K emails to unknown recipients. My problem is postfix is accepting all of these emails into the mail queue then it generates bounces and of course those now sit in the queue. I have tweaked postfix with every known possible scenario on preventing backscatter and i know postfix by default is supposed to auto reject unkown recipients without accepting them into the mail queue, so why is my mail server acting like this? here is my

    # See /usr/share/postfix/ 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 $mail_name (Debian/GNU)
    biff = no
    # appending .domain is the MUA's job.
    append_dot_mydomain = no
    # Uncomment the next line to generate "delayed mail" warnings
    #delay_warning_time = 4h
    readme_directory = /usr/share/doc/postfix
    # TLS parameters
    smtpd_tls_cert_file = /etc/postfix/smtpd.cert
    smtpd_tls_key_file = /etc/postfix/smtpd.key
    smtpd_use_tls = yes
    smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
    smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
    # See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for
    # information on enabling SSL in the smtp client.
    myhostname =
    alias_maps = hash:/etc/aliases
    alias_database = hash:/etc/aliases
    myorigin = /etc/mailname
    mydestination =, localhost, localhost.localdomain
    relayhost = 
    mynetworks = [::1]/128
    mailbox_command = procmail -a "$EXTENSION"
    mailbox_size_limit = 0
    recipient_delimiter = +
    inet_interfaces = all
    html_directory = /usr/share/doc/postfix/html
    virtual_alias_domains = 
    virtual_alias_maps = proxy:mysql:/etc/postfix/, mysql:/etc/postfix/
    virtual_mailbox_domains = proxy:mysql:/etc/postfix/
    virtual_mailbox_maps = proxy:mysql:/etc/postfix/
    virtual_mailbox_base = /var/vmail
    virtual_uid_maps = static:5000
    virtual_gid_maps = static:5000
    smtpd_sasl_auth_enable = yes
    broken_sasl_auth_clients = yes
    smtpd_sasl_authenticated_header = yes
    smtpd_recipient_restrictions = permit_mynetworks, permit_sasl_authenticated, check_recipient_access mysql:/etc/postfix/, reject_unauth_destination, reject_invalid_hostname, reject_unauth_pipelining, reject_non_fqdn_sender, reject_non_fqdn_recipient,reject_unknown_sender_domain, reject_unknown_recipient_domain, reject_rbl_client, reject_rbl_client, reject_rbl_client, reject_rbl_client, reject_rbl_client, reject_rbl_client, reject_rbl_client, reject_rbl_client, permit
    smtpd_tls_security_level = may
    transport_maps = proxy:mysql:/etc/postfix/
    relay_domains = mysql:/etc/postfix/
    relay_recipient_maps = mysql:/etc/postfix/
    virtual_create_maildirsize = yes
    virtual_maildir_extended = yes
    virtual_mailbox_limit_maps = proxy:mysql:/etc/postfix/
    virtual_mailbox_limit_override = yes
    virtual_maildir_limit_message = "The user you are trying to reach is over quota."
    virtual_overquota_bounce = yes
    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
    smtpd_sender_restrictions = check_sender_access mysql:/etc/postfix/
    smtpd_client_restrictions = check_client_access mysql:/etc/postfix/
    maildrop_destination_concurrency_limit = 1
    maildrop_destination_recipient_limit = 1
    virtual_transport = maildrop
    header_checks = regexp:/etc/postfix/header_checks
    mime_header_checks = regexp:/etc/postfix/mime_header_checks
    nested_header_checks = regexp:/etc/postfix/nested_header_checks
    body_checks = regexp:/etc/postfix/body_checks
    content_filter = amavis:[]:10024
    receive_override_options = no_address_mappings
    message_size_limit = 0
    smtpd_delay_reject = yes
    smtpd_helo_restrictions = reject_invalid_hostname
    smtpd_helo_required = yes
    bounce_queue_lifetime = 1d
    maximal_queue_lifetime = 1d
    smtpd_timeout = 50s
    Last edited: Oct 18, 2011
  2. till

    till Super Moderator Staff Member ISPConfig Developer

    Do you use any alias email domains (dont mix up with alias email addresses)?

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