I have installed postfix, but for some time having trouble with it.
I am able to connect to port 25 on local host, but when I telnet port 25 from an external machine, the connection appears to be made but then hungs up.
I get the response:
421 Cannot connect to SMTP server xx.xxx.xx.xxx (xx.xx.xx.xxx:25), connect error 10061 Connection closed by foreign host.
I have inet_interfaces set to all.
main.cf
soft_bounce = no
queue_directory = /var/spool/postfix
command_directory = /usr/sbin
daemon_directory = /usr/libexec/postfix
data_directory = /var/lib/postfix
mail_owner = postfix
myhostname = mydomain.com
mydomain = mydomain.com
myorigin = $myhostname
inet_interfaces = all
inet_protocols = all
mydestination = $myhostname, localhost.$mydomain, localhost
unknown_local_recipient_reject_code = 550
mynetworks = 168.100.189.0/28, 127.0.0.0/8
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
home_mailbox = Maildir/
debug_peer_level = 2
debugger_command =
PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin
ddd $daemon_directory/$process_name $process_id & sleep 5
sendmail_path = /usr/sbin/sendmail.postfix
newaliases_path = /usr/bin/newaliases.postfix
mailq_path = /usr/bin/mailq.postfix
setgid_group = postdrop
html_directory = no
manpage_directory = /usr/share/man
sample_directory = /usr/share/doc/postfix-2.10.1/samples
readme_directory = /usr/share/doc/postfix-2.10.1/README_FILES
smtpd_sasl_auth_enable = yes
broken_sasl_auth_clients = yes
smtpd_sasl_type = dovecot
smtpd_sasl_path = private/auth
smtpd_sasl_security_options = noanonymous
master.cf
smtp inet n - n - - smtpd
submission inet n - n - - smtpd
-o syslog_name=postfix/submission
smtps inet n - n - - smtpd
pickup unix n - n 60 1 pickup
cleanup unix n - n - 0 cleanup
qmgr unix n - n 300 1 qmgr
tlsmgr unix - - n 1000? 1 tlsmgr
rewrite unix - - n - - trivial-rewrite
bounce unix - - n - 0 bounce
defer unix - - n - 0 bounce
trace unix - - n - 0 bounce
verify unix - - n - 1 verify
flush unix n - n 1000? 0 flush
proxymap unix - - n - - proxymap
proxywrite unix - - n - 1 proxymap
smtp unix - - n - - smtp
relay unix - - n - - smtp
showq unix n - n - - showq
error unix - - n - - error
retry unix - - n - - error
discard unix - - n - - discard
local unix - n n - - local
virtual unix - n n - - virtual
lmtp unix - - n - - lmtp
anvil unix - - n - 1 anvil
scache unix - - n - 1 scache
netstat -plnt | grep 25
tcp 0 0 0.0.0.0:25 0.0.0.0:* LISTEN 10742/master
tcp6 0 0 :::25 :::* LISTEN 10742/master
Incoming connections to smtp port may be blocked by a firewall.
You may try to use tools like tcptraceoute to locate such firewalls.