Postfix Relay Servers behind ELB in AWS
I have three Relay Servers in a Cluster Sitting behind and ELB. The internal servers on the network connect to the ELB and send their SMTP traffic. The traffic is then routed to the Relay Server which is then sent to the destination Relay Servers. I've been able to confirm this functionality through TelNet, however when I changed the postfix configuration to point to the ELB in the main.cf, I am not able to connect to the Relay Servers. I'm not sure what the issue is: Below is my configuration in main.cf:
# RR: Mon Apr 29, 2013 => added 72.172.71.2/32 to support (LA) Duo VPN
queue_directory = /var/spool/postfix
command_directory = /usr/sbin
daemon_directory = /usr/libexec/postfix
mail_owner = postfix
myhostname = test.com
mydomain = test.com
inet_interfaces = all
mydestination = $myhostname, localhost.$mydomain, localhost
smtpd_delay_reject = yes
smtpd_helo_required = yes
soft_bounce = no
strict_rfc821_envelopes = yes
local_header_rewrite_clients = permit_mynetworks
smtp_generic_maps = pcre:/etc/postfix/generic
unknown_local_recipient_reject_code = 550
broken_sasl_auth_clients = no
smtpd_sasl_application_name = smtpd
smtpd_sasl_auth_enable = no
smtpd_sasl_local_domain =
smtpd_sasl_security_options = noanonymous
#tls_random_source = dev:/dev/urandom
#smtpd_tls_security_level = may
mailbox_size_limit = 102400000
message_size_limit = 51200000
queue_minfree = 76800000
smtpd_client_restrictions =
permit_mynetworks,
permit_sasl_authenticated,
reject_unknown_client
smtpd_helo_restrictions =
permit_mynetworks,
permit_sasl_authenticated,
reject_invalid_hostname,
reject_non_fqdn_hostname
smtpd_sender_restrictions =
permit_mynetworks,
permit_sasl_authenticated,
reject_unlisted_sender,
reject_non_fqdn_sender,
reject_unknown_sender_domain
smtpd_recipient_restrictions =
permit_mynetworks,
permit_sasl_authenticated,
reject_unlisted_recipient,
reject_non_fqdn_recipient,
reject_unauth_destination,
reject_unknown_recipient_domain
# check_recipient_access hash:/etc/postfix/filtered_domains
smtpd_data_restrictions =
permit_mynetworks,
reject_unauth_pipelining,
permit_sasl_authenticated
smtpd_end_of_data_restrictions =
unknown_local_recipient_reject_code = 550
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
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
#inet_protocols = all
postscreen_upstream_proxy_protocol = haproxy
master.cf:
#
# Postfix master process configuration file. For details on the format
# of the file, see the master(5) manual page (command: "man 5 master").
#
# ==========================================================================
# service type private unpriv chroot wakeup maxproc command + args
# (yes) (yes) (yes) (never) (100)
# ==========================================================================
smtp inet n - n - - smtpd
submission inet n - n - - smtpd
# -o smtpd_enforce_tls=yes
-o smtpd_sasl_auth_enable=yes
# -o smtpd_client_restrictions=permit_sasl_authenticated,reject
#smtps inet n - n - - smtpd
# -o smtpd_tls_wrappermode=yes
# -o smtpd_sasl_auth_enable=yes
# -o smtpd_client_restrictions=permit_sasl_authenticated,reject
#628 inet n - n - - qmqpd
pickup fifo n - n 60 1 pickup
cleanup unix n - n - 0 cleanup
qmgr fifo n - n 300 1 qmgr
#qmgr fifo n - n 300 1 oqmgr
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
# When relaying mail as backup MX, disable fallback_relay to avoid MX loops
relay unix - - n - - smtp
-o fallback_relay=
# -o smtp_helo_timeout=5 -o smtp_connect_timeout=5
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
#
# ====================================================================
# Interfaces to non-Postfix software. Be sure to examine the manual
# pages of the non-Postfix software to find out what options it wants.
#
# Many of the following services use the Postfix pipe(8) delivery
# agent. See the pipe(8) man page for information about ${recipient}
# and other message envelope options.
# ====================================================================
#
# maildrop. See the Postfix MAILDROP_README file for details.
# Also specify in main.cf: maildrop_destination_recipient_limit=1
#
maildrop unix - n n - - pipe
flags=DRhu user=vmail argv=/usr/local/bin/maildrop -d ${recipient}
#
# The Cyrus deliver program has changed incompatibly, multiple times.
#
old-cyrus unix - n n - - pipe
flags=R user=cyrus argv=/usr/lib/cyrus-imapd/deliver -e -m ${extension} ${user}
# Cyrus 2.1.5 (Amos Gouaux)
# Also specify in main.cf: cyrus_destination_recipient_limit=1
cyrus unix - n n - - pipe
user=cyrus argv=/usr/lib/cyrus-imapd/deliver -e -r ${sender} -m ${extension} ${user}
#
# See the Postfix UUCP_README file for configuration details.
#
uucp unix - n n - - pipe
flags=Fqhu user=uucp argv=uux -r -n -z -a$sender - $nexthop!rmail ($recipient)
#
# Other external delivery methods.
#
ifmail unix - n n - - pipe
flags=F user=ftn argv=/usr/lib/ifmail/ifmail -r $nexthop ($recipient)
bsmtp unix - n n - - pipe
flags=Fq. user=foo argv=/usr/local/sbin/bsmtp -f $sender $nexthop $recipient
This is what I see in the relay server maillog:
AED0D6093E: message-id=<20170420163035.AED0D6093E<test.com>
And on the mail client it's saying undeliverable. Please let me know if anyone understands what might be going on.
Solution 1:
I was able to make Postfix see client IP addresses behind an NLB, by checking "Preserve client IP addresses" in the target group attributes. No need to use HAproxy or activate proxy protocol v2.