Take the 2-minute tour ×
Server Fault is a question and answer site for professional system and network administrators. It's 100% free, no registration required.

HI I have problem when I want to restart Postfix, my postfix server has send email to another mail address without permission, actually I give permission for postfix send mail using virtual Mailbox.

I don't know what happen, example I have domain.com and I am giving cs@domain.com permission to send and receive mail, but sometimes I have mailbox in my local directory /vmail/domain.com/unknown1@domain.com, unknow2@domain.com ,ect

and postfix try to send massive email to random mail server (yahoo,aol,google,ect).

This is Spam or Viruses ? Do you have suggestion for Solve this problem ?

this is my config /etc/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 (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 = domain.com
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
myorigin = /etc/mailname
mydestination = localhost, localhost.localdomain 
relayhost = 
mynetworks =
mailbox_command = procmail -a "$EXTENSION"
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = all
html_directory = /usr/share/doc/postfix/html
message_size_limit = 30720000
virtual_alias_domains = 
virtual_alias_maps = proxy:mysql:/etc/postfix/mysql-virtual_forwardings.cf, mysql:/etc/postfix/mysql-virtual_email2email.cf
virtual_mailbox_domains = proxy:mysql:/etc/postfix/mysql-virtual_domains.cf
virtual_mailbox_maps = proxy:mysql:/etc/postfix/mysql-virtual_mailboxes.cf
virtual_mailbox_base = /home/vmail
virtual_uid_maps = static:5000
virtual_gid_maps = static:5000
local_transport = dovecot
local_recipient_maps =  $virtual_mailbox_maps
smtpd_sasl_auth_enable = yes
broken_sasl_auth_clients = yes
smtpd_sasl_authenticated_header = yes
smtpd_error_sleep_time = 1s
smtpd_soft_error_limit = 10
smtpd_hard_error_limit = 20
#clamav antivirus
content_filter = scan:
receive_override_options = no_address_mappings
#add anti spam measure
smtpd_client_restrictions =
smtpd_helo_restrictions =
smtpd_sender_restrictions =
smtpd_helo_required = yes
strict_rfc821_envelopes = yes
disable_vrfy_command = yes
unknown_address_reject_code  = 554
unknown_hostname_reject_code = 554
unknown_client_reject_code   = 554
smtpd_recipient_restrictions = reject_unauth_destination,
    reject_rbl_client blackholes.easynet.nl,
    reject_rbl_client cbl.abuseat.org,
    reject_rbl_client bl.spamcop.net,
    reject_rbl_client zen.spamhaus.org,  
    reject_rbl_client opm.blitzed.org,
    check_sender_access hash:/etc/postfix/filtered_domains,
    reject_rbl_client dnsbl.njabl.org,
    reject_rbl_client list.dsbl.org,
    reject_rbl_client multihop.dsbl.org,
    reject_rbl_client dul.dnsbl.sorbs.net,
smtpd_data_restrictions =
#stop denial of attack
default_process_limit = 100
smtpd_client_connection_count_limit = 10
smtpd_client_connection_rate_limit = 30
header_size_limit = 51200
smtp_recipient_limit = 100

virtual_create_maildirsize = yes
virtual_maildir_extended = 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
virtual_transport = dovecot-spamass
dovecot_destination_recipient_limit = 1
share|improve this question
maybe someone use your server as open relay cyberciti.biz/tips/test-mail-server-for-an-open-relay.html abuse.net/relay.html –  c4f4t0r Sep 4 '13 at 6:11
i think my server not open relay, I have been test and the result is "Relay Access denied" –  viyancs Sep 4 '13 at 6:19
i never recived mail named unknow1 and unknow2 in my mailserver, so check where come from that mails –  c4f4t0r Sep 4 '13 at 6:43
thatis just sample name , actualy name will be different example alex@balbalal...just sample –  viyancs Sep 4 '13 at 7:05
Do you have any website on the server? Add full log of "fake" sending to the question –  ALex_hha Sep 4 '13 at 7:09
show 1 more comment

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.