sendmail can not relay mail to exchange server

[Arunabha Banerjee]

My goal is to be able to send all email through my Linux server using sendmail, to Exchange Server. I have added Exchange Server entry in /etc/mail/sendmail.cf file but still it is relaying to localhost.localdomain.

Red Hat OS

[root@vburplsmtp06 root]# cat /etc/redhat-release
Red Hat Enterprise Linux ES release 3 (Taroon Update 8)

 sendmail version

[root@vburplsmtp06 root]# rpm -qa | grep -i sendmail*
sendmail-cf-8.12.11-4.RHEL3.6
sendmail-8.12.11-4.RHEL3.6

RelayHost entry in sendmail.cf file

[root@vburplsmtp06 root]# cat /etc/mail/sendmail.cf | grep -e DS
DSmailhost
# Return-Receipt-To: header implies DSN request
# DHParameters (only required if DSA/DH is used)

/etc/hosts file

[root@vburplsmtp06 mail]# cat /etc/hosts
# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1       localhost.localdomain   localhost
146.178.24.70   vburplsmtp06    mail2.alinta.net.au
146.178.73.228  mailhost

resolv.conf

[root@vburplsmtp06 root]# cat /etc/resolv.conf
domain alinta.net.au
search alinta.net.au ue.com.au
nameserver 218.185.65.254
nameserver 203.94.140.38
nameserver 203.94.129.130
nameserver 146.178.22.217
nameserver 146.178.73.217

/var/log/maillog output

Aug 13 21:29:41 vburplsmtp06 sm-msp-queue[19707]: p7D6jqcT014362: p7DBQp1j019707: sender notify: Warning: could not send message for past 4 hours
Aug 13 21:29:41 vburplsmtp06 sendmail[19734]: alias database /etc/aliases.db out of date
Aug 13 21:29:41 vburplsmtp06 sendmail[19734]: p7DBSiEX019734: from=<>, size=10664, class=0, nrcpts=1, msgid=<201108131129.p7DBQp1j019707@mail2.alinta.net.au>, proto=ESMTP, daemon=MTA, relay=localhost.localdomain [127.0.0.1]

Tried to send mail manually and it is pointing relayhost to localhost.localdomain

[root@vburplsmtp06 root]# sendmail -v root
test
.
root... Connecting to [127.0.0.1] via relay...
220 mail2.alinta.net.au ESMTP Sendmail 8.12.11.20060308/8.12.11; Sat, 13 Aug 2011 20:48:54 +1000
>>> EHLO mail2.alinta.net.au
250-mail2.alinta.net.au Hello localhost.localdomain [127.0.0.1], pleased to meet you
250-ENHANCEDSTATUSCODES
250-PIPELINING
250-8BITMIME
250-SIZE
250-DSN
250-ETRN
250-AUTH GSSAPI
250-DELIVERBY
250 HELP
>>> MAIL From:<abanerjee@mail2.alinta.net.au> SIZE=5 AUTH=abanerjee@mail2.alinta.net.au
250 2.1.0 <abanerjee@mail2.alinta.net.au>... Sender ok
>>> RCPT To:<root@mail2.alinta.net.au>
>>> DATA
250 2.1.5 <root@mail2.alinta.net.au>... Recipient ok
354 Enter mail, end with "." on a line by itself
>>> .
250 2.0.0 p7DAmsYo019039 Message accepted for delivery
root... Sent (p7DAmsYo019039 Message accepted for delivery)
Closing connection to [127.0.0.1]
>>> QUIT
221 2.0.0 mail2.alinta.net.au closing connection

 Tried to send mail manually through Exchange Server (mailhost - 146.178.73.228) and I got the mail in my mailbox.

[root@vburplsmtp06 root]# telnet mailhost 25
Trying 146.178.73.228...
Connected to mailhost (146.178.73.228).
Escape character is '^]'.
220 VTALPWSMTP05.alinta.net.int Microsoft ESMTP MAIL Service, Version: 6.0.3790.4675 ready at  Sat, 13 Aug 2011 21:49:41 +1000
HELO
250 VTALPWSMTP05.alinta.net.int Hello [146.178.24.70]
MAIL FROM: root@vburplsmtp06
250 2.1.0 root@vburplsmtp06....Sender OK
RCPT TO: barunab@maxis.com.my
250 2.1.5 barunab@maxis.com.my
DATA
354 Start mail input; end with <CRLF>.<CRLF>
This is a test mail
.
250 2.6.0 <VTALPWSMTP05WEsBk310000137e@VTALPWSMTP05.alinta.net.int> Queued mail for delivery
QUIT
221 2.0.0 VTALPWSMTP05.alinta.net.int Service closing transmission channel
Connection closed by foreign host.

So why sendmail is always pointing "relay=localhost.localdomain [127.0.0.1]" why not "mailhost" after adding the "DSmailhost" entry

Please help.

[Naj]

Hi,

Could you please paste configuration for

#more /etc/mail/access

Thanks

BR
Naj

[Arunabha Banerjee]

Please find /etc/mail/access entry as below

[root@vburplsmtp06 root]# cat /etc/mail/access
# Check the /usr/share/doc/sendmail/README.cf file for a description
# of the format of this file. (search for access_db in that file)
# The /usr/share/doc/sendmail/README.cf is part of the sendmail-doc
# package.
#
# by default we allow relaying from localhost...
localhost.localdomain           RELAY
localhost                       RELAY
127.0.0.1                       RELAY

[Naj]

Hi,

How about sendmail.mc file configuration, did you add relay server there?

#vi sendmail.mc

dnl define(`SMART_HOST',`smtp.your.provider')dnl

replace your mail exchange server as below

define(`SMART_HOST',`exchange-server name')

::save configuration

# m4 /etc/mail/sendmail.mc > /etc/mail/sendmail.cf

Thanks

BR

Naj

[Arunabha Banerjee]

This entry I have added already.

[root@vburplsmtp06 mail]# cat sendmail.mc | grep -e mailhost
define(`SMART_HOST',`mailhost')
[root@vburplsmtp06 mail]#

[Matti_Kurkela]

In /etc/hosts, you have told "mail2.alinta.net.au" is an alias for vburplsmtp06.

Your test message is addressed to "abanerjee@mail2.alinta.net.au". Because the destination hostname matches one of the aliases of the local host, our sendmail will notice this is supposed to be a local recipient, so there is no reason to use a smarthost. It will attempt to deliver the mail locally, typically to Unix mailbox file /var/mail/abanerjee (assuming that such an user exists on the system).

The "forwarding to localhost" happens because in RHEL 3 and newer, Sendmail runs as two separate processes:

# ps -ef |grep send
root      4078     1  0 Jul04 ?        00:01:59 sendmail: accepting connections
smmsp     4087     1  0 Jul04 ?        00:00:00 sendmail: Queue runner@01:00:00 

 All the messages are first forwarded to the local Sendmail queue runner process, which will then make the necessary outgoing connections and/or invoke the local delivery agent as necessary.

If you want absolutely all mail (even the messages addressed to local recipients) to go to exchange server, you should add

define(`MAIL_HUB',`mailhost')

 to your sendmail.mc, and then regenerate your sendmail.cf using these commands:

cd /etc/mail
make

 (The /etc/mail/Makefile contains instructions for the "make" command, including the correct m4 command line for regenerating the sendmail.cf using the sendmail.mc as a template.)

Sendmail's logic works out like this:

1. Is MAIL_HUB set? If yes, send message to MAIL_HUB server for further delivery; otherwise continue.
2. Is the destination address local? If yes, then deliver locally; otherwise continue.
3. Is SMART_HOST set? If yes, send message to SMART_HOST server for further delivery; otherwise continue.
4. (all the other steps required to find and contact a remote mail server over the Internet)

If you use MAIL_HUB, your Exchange server must be prepared to accept and handle incoming messages addressed to destinations like "root@mail2.alinta.net.au", "root@vburplsmtp06" or maybe even just "root" in some meaningful fashion.

[Arunabha Banerjee]

Hi Matti,

Thanks for the explantaion. But after implementing the steps "define(`MAIL_HUB',`mailhost')" still I am facing the same problem.

[Wilfred Chau_1]

If you use an IP of the exchange server for the DS directive, can you relay mail?

[tuxy]

Did you resolved the problem or it is still appears?