Next message: Charles Marcus: "Re: Siteoverride & Sender Restrictions"
Hi All,
Been struggling with this one for too long.
Mail to yahoo.com and a few other isolated locations are timeing out mid
stream. All other destinations - No prob's.
Small plain text is OK. Add a 15K gif attachement => timeout.
One other common denominator is that the problem recipient mail servers don't
like ehlo, so I'm suspecting some protocol issue. Detected using telnet.
To test I've disabled tls and ehlo, but this is not the solution.
Sendmail has no issues sending from the same node, so it's not likely to be a
network related issue. (SNAT'd to the same address)
tcpdump shows the standard transfer for the first 2-3 secs, Syn => ACK =>ACK
PUSH, then 2 minutes of outbound packets with no reply, then a couple of
inbound push before a FIN following a suspected timeout length of 2 minutes.
tcpsump on external interface of firewall is consistent with other dumps.
This case in particular is a secondary instance to bypass filters for outbound
mail, but the issue persists with either instance even when the other is not
running.
The main.cf is reduced to minimal...
postconf -n
alias_database = hash:/etc/aliases
alias_maps = hash:/etc/aliases
append_dot_mydomain = no
biff = no
config_directory = /etc/postfix-out/
inet_interfaces = xxx.xxx.xxx.xxx
initial_destination_concurrency = 2
mailbox_size_limit = 0
mydestination = mail.eml.com.au, mailout.xxxxl localhost.xxx, localhost
myhostname = mailout.eml.local
mynetworks = xxx.xxx.xxx.xxx/32, 127.0.0.0/8, [::ffff:127.0.0.0]/104
[::1]/128
myorigin = /etc/mailname
queue_directory = /var/spool/postfix-out
readme_directory = no
recipient_delimiter = +
smtp_tls_per_site = hash:/etc/postfix/smtp_tls_per_site
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
smtpd_banner = $myhostname ESMTP $mail_name
smtpd_client_restrictions = permit_mynetworks, reject
smtpd_recipient_restrictions = permit_mynetworks, reject_unauth_destination,
reject_invalid_hostname, permit
smtpd_tls_cert_file = /etc/ssl/certs/ssl-cert-snakeoil.pem
smtpd_tls_key_file = /etc/ssl/private/ssl-cert-snakeoil.key
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtpd_use_tls = no
This is bizarre.
Anyone got any ideas?
Cheers,
--
Lew
