Hello everybody,
I've two servers with Rhel 5.9 and Postfix 2.3.3 installed.
Each Postfix server relay all emails, received from 20 clients, to a
main smptd server with about 200/400 emails in one minute all days
during heavy load hours
This is the main.cf configured
queue_directory = /queue/SmtpB
queue_run_delay = 150s
minimal_backoff_time = 150s
maximal_backoff_time = 300s
command_directory = /usr/sbin
daemon_directory = /usr/libexec/postfix
mail_owner = postfix
myhostname = smtp02.xxx.xxx
inet_interfaces = xxx.xxx.xxx.xxx
mydestination = $myhostname, localhost.$mydomain, localhost
unknown_local_recipient_reject_code = 550
mynetworks = xxx.xxx.xxx.0/24, 127.0.0.0/8
smtpd_relay_restrictions = permit_mynetworks
disable_dns_lookups = yes
relayhost = [smtp.xxx.it]
alias_maps = hash:/queue/SmtpB/etc/aliases
alias_database = hash:/queue/SmtpB/etc/aliases
mail_spool_directory = /queue/SmtpB/mail
header_checks = regexp:/queue/SmtpB/etc/postfix/header_checks
smtpd_banner = $myhostname ESMTP $mail_name Relay
default_destination_concurrency_limit = 8
debug_peer_level = 2
debugger_command =
PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin
xxgdb $daemon_directory/$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-2.3.3/samples
readme_directory = /usr/share/doc/postfix-2.3.3/README_FILES
and master.cf
# ==========================================================================
# service type private unpriv chroot wakeup maxproc command + args
# (yes) (yes) (yes) (never) (100)
# ==========================================================================
smtp inet n - n - - smtpd
pickup fifo n - n 60 1 pickup
cleanup unix n - n - 0 cleanup
qmgr fifo 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
smtp unix - - n - - smtp -o
smtp_bind_address=xxx.xxx.xxx.xxx
relay unix - - n - - smtp
-o fallback_relay=
showq unix n - n - - showq
error 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
During one day the server deliveries about 40.000 emails, but during
working hours I receive repeated random periods where the Postfix smtp
client doesn't open any socket to destination main SMTPD server and the
maillog file write
dsn=4.4.2, status=deferred (conversation with
smtp.xxx.it[xxx.xx.xxx.xxx] timed out while sending MAIL FROM)
This behavior continues for about 5 minutes and on the next queue
manager run, all emails will be accepted and delivered.
At first time I though the problem was on the destination SMTP server,
but running tcpdump during "deferred" the server didn't open any socket.
Any idea to understand and fix this behavior?
Regards,
Roberto.
