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sendmail configuration to relay to hosted exchange server via SSL

el_cuco asked
Medium Priority
Last Modified: 2013-12-17

I've been trying to tackle a setup for the past few days with my sendmail server.  I need to relay emails to our exchange server for proper delivery to my users.  Our hosted server allows Relay using SSL.  I've configured a user on the exchange side to allow relay which would be used by my sendmail config.

Currently the issue that i'm having is that though i've generated the needed certs I see through the maillog that sendmail is not finding them.  
eb  9 10:04:32 watchdog sendmail[28172]: NOQUEUE: stopping daemon, reason=signal
Feb  9 10:04:33 watchdog sendmail[28252]: alias database /etc/aliases rebuilt by elcuco
Feb  9 10:04:33 watchdog sendmail[28252]: /etc/aliases: 82 aliases, longest 90 bytes, 1350 bytes total
Feb  9 10:04:33 watchdog sendmail[28257]: starting daemon (8.13.8): SMTP+queueing@01:00:00
Feb  9 10:04:33 watchdog sendmail[28257]: STARTTLS: CRLFile missing
Feb  9 10:04:33 watchdog sendmail[28257]: STARTTLS=server, Diffie-Hellman init, key=512 bit (1)
Feb  9 10:04:33 watchdog sendmail[28257]: STARTTLS=server, init=1

Feb  9 10:04:45 watchdog sendmail[28270]: STARTTLS: ClientCertFile missing
Feb  9 10:04:45 watchdog sendmail[28270]: STARTTLS: ClientKeyFile missing
Feb  9 10:04:45 watchdog sendmail[28270]: STARTTLS: CRLFile missing
Feb  9 10:04:45 watchdog sendmail[28270]: STARTTLS=client, init=1

I've been reading a significant amount of posts on configuring sendmail to use ssl to relay but at this point i'm pretty confused as to what I may be missing.

I'm using Centos 5 / sendmail 8.13.8

The config parameters i've added to the .mc file are

define(`confCACERT_PATH', `/etc/mail/certs')dnl
define(`confCACERT', `/etc/mail/certs/ca.crt')dnl
define(`confSERVER_CERT', `/etc/mail/certs/sendmail.crt')dnl
define(`confSERVER_KEY', `/etc/mail/certs/sendmail.key')dnl
define(`confTLS_SRV_OPTIONS', `V')

DAEMON_OPTIONS(`Name=smtps,Port=smtps, Modifiers=s')

define(`SMART_HOST', `smtpx1.my.net') (relay hostname)

I've also added the authenticated user account needed to talk to exchange server under the authinfo file.

AuthInfo:smtp1.my.net "U:ti@hostname.com" "P:Passw@rd" "M:PLAIN"
AuthInfo: "U:ti@hostname.com" "P:Passw@rd1" "M:PLAIN"

Any ideas or suggestions i should be following on this?


Watch Question

SurajSenior System Engineer

unfortunately the exchange server is a hosted server which i do not have access to as far as the internals are concerned.   All i want to accomplish here is to be able to relay to that exchange server using an ssl connection with an authenticated user which is hosted on the exchange side originating from my sendmail server.

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