Eu instalei o postfix e o devcot em um dos meus servidores ativos para enviar e-mails em massa (mensagens do sistema na inscrição, senhas incorretas etc.). Eu uso a função php_imap para verificar os retornos e sinalizar os IDs de e-mail para que não continuemos enviando e-mails para esses endereços que resultaram em uma rejeição. Notei que a função php_imap não estava lendo as rejeições nos servidores ao vivo que lia os saltos nos servidores de teste. Mas o servidor ao vivo é capaz de enviar e-mails! Ambos os servidores têm o mesmo sistema operacional Centos 6.4 e possuem a mesma configuração de iptable.
Eu comparei as entradas de DNS dos domínios "teste" e "ao vivo" e eles têm as entradas de SPF necessárias. O provedor de hospedagem tem os registros PTR necessários. Mas os saltos por algum motivo não estavam disponíveis para o programa php_imap.
Neste ponto, eu não tinha certeza se as rejeições estavam sendo entregues ao servidor e o dovecot não podia lê-las ou se as rejeições não foram entregues.
Então eu comparei as entradas em /etc/postfix/main.cf e /etc/postfix/master.cf dos servidores "test" e "live" e descobri que elas são as mesmas, exceto pelo nome do domínio.
Para ter certeza, verifiquei se o postfix está executando ps aux | grep postfix e ele retornou
[root@bw sridhar]# ps aux | grep postfix
root 1433 0.0 0.1 13476 2696 ? Ss 09:32 0:00 /usr/libexec/postfix/master
postfix 1443 0.0 0.1 13720 2836 ? S 09:32 0:00 qmgr -l -t fifo -u
postfix 4724 0.0 0.1 13552 2668 ? S 12:00 0:00 pickup -l -t fifo -u
postfix 4850 0.0 0.1 13696 2776 ? S 12:15 0:00 cleanup -z -t unix -u
postfix 4852 0.0 0.1 13748 2928 ? S 12:15 0:00 smtp -t unix -u
postfix 4855 0.0 0.1 13748 2928 ? S 12:15 0:00 smtp -t unix -u
postfix 4856 0.0 0.1 13588 2656 ? S 12:15 0:00 bounce -z -n defer -t unix -u
root 4858 0.0 0.0 4360 736 pts/0 S+ 12:15 0:00 grep postfix
[root@bwStagingTesting sridhar]# ps aux | grep postfix
root 1258 0.0 0.2 12816 2480 ? Ss Feb17 0:13 /usr/libexec/postfix/master
postfix 1268 0.0 0.2 13228 2896 ? S Feb17 0:07 qmgr -l -t fifo -u
postfix 2158 0.0 0.2 12888 2468 ? S Feb17 0:00 tlsmgr -l -t unix -u
postfix 4860 0.0 0.2 12892 2496 ? S 12:12 0:00 pickup -l -t fifo -u
postfix 4988 0.0 0.2 13036 2604 ? S 12:15 0:00 cleanup -z -t unix -u
postfix 4990 0.0 0.3 13148 3096 ? S 12:15 0:00 local -t unix
root 5334 0.0 0.0 4356 728 pts/5 S+ 12:15 0:00 grep postfix
Parece OK para mim. Em seguida, verifiquei se sou capaz de fazer telnet no host local para a porta 25 e obtive os seguintes resultados
[root@bw sridhar]# telnet localhost 25
Trying ::1...
telnet: connect to address ::1: Connection refused
Trying 127.0.0.1...
telnet: connect to address 127.0.0.1: Connection refused
[root@bwStagingTesting sridhar]# telnet localhost 25
Trying ::1...
Connected to localhost.
Escape character is '^]'.
220 mail.st.biz ESMTP Postfix
ehlo localhost
250-mail.st.biz
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
quit
221 2.0.0 Bye
Connection closed by foreign host.
Eu tentei telnet para os endereços IP dos respectivos servidores do meu laptop. Telnet para o servidor LIVE resultou em telnet: Não é possível conectar-se ao host remoto: Conexão recusada
No entanto, posso fazer telnet para o servidor de teste.
Então eu verifiquei se alguém está ouvindo na porta 25 nas duas máquinas e no servidor ao vivo eu recebo o seguinte
[root@bw sridhar]# netstat -lnp | grep 25
unix 2 [ ACC ] STREAM LISTENING 8125 1341/dovecot /var/run/dovecot/login/pop3
unix 2 [ ACC ] STREAM LISTENING 8425 1433/master public/cleanup
tcp 0 0 0.0.0.0:25 0.0.0.0:* LISTEN 1258/master
tcp 0 0 :::25 :::* LISTEN 1258/master
unix 2 [ ACC ] STREAM LISTENING 8270 1258/master public/cleanup
unix 2 [ ACC ] STREAM LISTENING 8277 1258/master private/tlsmgr
unix 2 [ ACC ] STREAM LISTENING 8281 1258/master private/rewrite
unix 2 [ ACC ] STREAM LISTENING 8285 1258/master private/bounce
unix 2 [ ACC ] STREAM LISTENING 8289 1258/master private/defer
unix 2 [ ACC ] STREAM LISTENING 8293 1258/master private/trace
unix 2 [ ACC ] STREAM LISTENING 8297 1258/master private/verify
unix 2 [ ACC ] STREAM LISTENING 8301 1258/master public/flush
unix 2 [ ACC ] STREAM LISTENING 8305 1258/master private/proxymap
unix 2 [ ACC ] STREAM LISTENING 8309 1258/master private/proxywrite
unix 2 [ ACC ] STREAM LISTENING 8313 1258/master private/smtp
unix 2 [ ACC ] STREAM LISTENING 8317 1258/master private/relay
unix 2 [ ACC ] STREAM LISTENING 8321 1258/master public/showq
unix 2 [ ACC ] STREAM LISTENING 8325 1258/master private/error
unix 2 [ ACC ] STREAM LISTENING 8329 1258/master private/retry
unix 2 [ ACC ] STREAM LISTENING 8333 1258/master private/discard
unix 2 [ ACC ] STREAM LISTENING 8337 1258/master private/local
unix 2 [ ACC ] STREAM LISTENING 8341 1258/master private/virtual
unix 2 [ ACC ] STREAM LISTENING 8345 1258/master private/lmtp
unix 2 [ ACC ] STREAM LISTENING 8349 1258/master private/anvil
unix 2 [ ACC ] STREAM LISTENING 8353 1258/master private/scache
Eu vejo que as duas primeiras linhas exibidas para o TEST SERVER estão faltando nas entradas para o servidor LIVE. O que significa que o postfix não está escutando na porta 25 no servidor LIVE Isso me fez pensar se isso poderia ser a razão pela qual as rejeições não estão chegando ao servidor LIVE, mas estão chegando ao servidor de teste.
Estou nisso há dois dias e ainda não encontrei uma pista sobre como consertar isso. Alguma idéia de como posso resolver isso?
[root@bw sridhar]# iptables -L
Chain INPUT (policy DROP)
target prot opt source destination
ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED
DROP tcp -- anywhere anywhere tcp flags:FIN,SYN,RST,PSH,ACK,URG/NONE
DROP tcp -- anywhere anywhere tcp flags:!FIN,SYN,RST,ACK/SYN state NEW
DROP tcp -- anywhere anywhere tcp flags:FIN,SYN,RST,PSH,ACK,URG/FIN,SYN,RST,PSH,ACK,URG
ACCEPT all -- anywhere anywhere
ACCEPT tcp -- anywhere anywhere tcp dpt:http
ACCEPT tcp -- anywhere anywhere tcp dpt:https
ACCEPT tcp -- anywhere anywhere tcp dpt:distinct
ACCEPT tcp -- anywhere anywhere tcp dpt:smtp
ACCEPT tcp -- anywhere anywhere tcp dpt:urd
ACCEPT tcp -- anywhere anywhere tcp dpt:pop3
ACCEPT tcp -- anywhere anywhere tcp dpt:pop3s
ACCEPT tcp -- anywhere anywhere tcp dpt:imap
ACCEPT tcp -- anywhere anywhere tcp dpt:imaps
Chain FORWARD (policy ACCEPT)
target prot opt source destination
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
[root@bwStagingTesting sridhar]# iptables -L
Chain INPUT (policy DROP)
target prot opt source destination
ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED
DROP tcp -- anywhere anywhere tcp flags:FIN,SYN,RST,PSH,ACK,URG/NONE
DROP tcp -- anywhere anywhere tcp flags:!FIN,SYN,RST,ACK/SYN state NEW
DROP tcp -- anywhere anywhere tcp flags:FIN,SYN,RST,PSH,ACK,URG/FIN,SYN,RST,PSH,ACK,URG
ACCEPT all -- anywhere anywhere
ACCEPT tcp -- anywhere anywhere tcp dpt:http
ACCEPT tcp -- anywhere anywhere tcp dpt:https
ACCEPT tcp -- anywhere anywhere tcp dpt:smtp
ACCEPT tcp -- anywhere anywhere tcp dpt:urd
ACCEPT tcp -- anywhere anywhere tcp dpt:pop3
ACCEPT tcp -- anywhere anywhere tcp dpt:pop3s
ACCEPT tcp -- anywhere anywhere tcp dpt:imap
ACCEPT tcp -- anywhere anywhere tcp dpt:imaps
ACCEPT tcp -- anywhere anywhere tcp dpt:distinct
ACCEPT tcp -- anywhere anywhere tcp dpt:munin
Chain FORWARD (policy ACCEPT)
target prot opt source destination
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
[root@bookingwire sridhar]# iptables -L --verbose
Chain INPUT (policy DROP 1662 packets, 103K bytes)
pkts bytes target prot opt in out source destination
184K 190M ACCEPT all -- any any anywhere anywhere state RELATED,ESTABLISHED
0 0 DROP tcp -- any any anywhere anywhere tcp flags:FIN,SYN,RST,PSH,ACK,URG/NONE
7 400 DROP tcp -- any any anywhere anywhere tcp flags:!FIN,SYN,RST,ACK/SYN state NEW
0 0 DROP tcp -- any any anywhere anywhere tcp flags:FIN,SYN,RST,PSH,ACK,URG/FIN,SYN,RST,PSH,ACK,URG
2140 128K ACCEPT all -- lo any anywhere anywhere
1176 67092 ACCEPT tcp -- any any anywhere anywhere tcp dpt:http
3 120 ACCEPT tcp -- any any anywhere anywhere tcp dpt:https
6 360 ACCEPT tcp -- any any anywhere anywhere tcp dpt:distinct
8 432 ACCEPT tcp -- any any anywhere anywhere tcp dpt:smtp
1 40 ACCEPT tcp -- any any anywhere anywhere tcp dpt:urd
2 88 ACCEPT tcp -- any any anywhere anywhere tcp dpt:pop3
38 2260 ACCEPT tcp -- any any anywhere anywhere tcp dpt:pop3s
1 40 ACCEPT tcp -- any any anywhere anywhere tcp dpt:imap
1 40 ACCEPT tcp -- any any anywhere anywhere tcp dpt:imaps
Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target prot opt in out source destination
Chain OUTPUT (policy ACCEPT 112K packets, 103M bytes)
pkts bytes target prot opt in out source destination
#
# Postfix master process configuration file. For details on the format
# of the file, see the master(5) manual page (command: "man 5 master").
#
# Do not forget to execute "postfix reload" after editing this file.
#
# ==========================================================================
# service type private unpriv chroot wakeup maxproc command + args
# (yes) (yes) (yes) (never) (100)
# ==========================================================================
submission inet n - n - - smtpd
-o smtpd_tls_security_level=encrypt
-o smtpd_sasl_auth_enable=yes
-o smtpd_client_restrictions=permit_sasl_authenticated,reject
-o milter_macro_daemon_name=ORIGINATING
#smtps inet n - n - - smtpd
# -o smtpd_tls_wrappermode=yes
# -o smtpd_sasl_auth_enable=yes
# -o smtpd_client_restrictions=permit_sasl_authenticated,reject
# -o milter_macro_daemon_name=ORIGINATING
#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
proxywrite unix - - n - 1 proxymap
smtp unix - - n - - smtp
# When relaying mail as backup MX, disable fallback_relay to avoid MX loops
relay unix - - n - - smtp
-o smtp_fallback_relay=
# -o smtp_helo_timeout=5 -o smtp_connect_timeout=5
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
#
# ====================================================================
# 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=bsmtp argv=/usr/local/sbin/bsmtp -f $sender $nexthop $recipient
#
#scalemail-backend unix - n n - 2 pipe
# flags=R user=scalemail argv=/usr/lib/scalemail/bin/scalemail-store
# ${nexthop} ${user} ${extension}
#
#mailman unix - n n - - pipe
# flags=FR user=list argv=/usr/lib/mailman/bin/postfix-to-mailman.py
# ${nexthop} ${user}
[root@bw sridhar]# netstat -lnp | grep master
tcp 0 0 0.0.0.0:587 0.0.0.0:* LISTEN 16536/master
tcp 0 0 :::587 :::* LISTEN 16536/master
unix 2 [ ACC ] STREAM LISTENING 152749 16536/master public/cleanup
unix 2 [ ACC ] STREAM LISTENING 152756 16536/master private/tlsmgr
unix 2 [ ACC ] STREAM LISTENING 152760 16536/master private/rewrite
unix 2 [ ACC ] STREAM LISTENING 152764 16536/master private/bounce
unix 2 [ ACC ] STREAM LISTENING 152768 16536/master private/defer
unix 2 [ ACC ] STREAM LISTENING 152772 16536/master private/trace
unix 2 [ ACC ] STREAM LISTENING 152776 16536/master private/verify
unix 2 [ ACC ] STREAM LISTENING 152780 16536/master public/flush
unix 2 [ ACC ] STREAM LISTENING 152784 16536/master private/proxymap
unix 2 [ ACC ] STREAM LISTENING 152788 16536/master private/proxywrite
unix 2 [ ACC ] STREAM LISTENING 152792 16536/master private/smtp
unix 2 [ ACC ] STREAM LISTENING 152796 16536/master private/relay
unix 2 [ ACC ] STREAM LISTENING 152800 16536/master public/showq
unix 2 [ ACC ] STREAM LISTENING 152804 16536/master private/error
unix 2 [ ACC ] STREAM LISTENING 152808 16536/master private/retry
unix 2 [ ACC ] STREAM LISTENING 152812 16536/master private/discard
unix 2 [ ACC ] STREAM LISTENING 152816 16536/master private/local
unix 2 [ ACC ] STREAM LISTENING 152820 16536/master private/virtual
unix 2 [ ACC ] STREAM LISTENING 152824 16536/master private/lmtp
unix 2 [ ACC ] STREAM LISTENING 152828 16536/master private/anvil
unix 2 [ ACC ] STREAM LISTENING 152832 16536/master private/scache
unix 2 [ ACC ] STREAM LISTENING 149905 16103/dovecot /var/run/dovecot/auth-master
[root@bw sridhar]# telnet localhost 587
Trying ::1...
Connected to localhost.
Escape character is '^]'.
220 mail.bookingwire.co.uk ESMTP Postfix
ehlo localhost
250-mail.bookingwire.co.uk
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-STARTTLS
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
quit
221 2.0.0 Bye
Connection closed by foreign host.
Como o Postfix é executado como "master", fiz o grep para o master no netstat. Observe as duas primeiras linhas que é óbvio que o postfix está escutando na porta 587. Eu, então, faço telnet para a porta 587 e verifiquei que minha suposição estava correta. Agora, o que eu não entendo é por que ouvir na porta 587 e como alterá-lo para escutar na porta 25