sendmail issue with relay host..

[MikeL_4]

We use a mail server called mailhost.convergys.com which I have coded in the sendmail.mc and submit.mc file as below...

[root@odccdds01 ~]# grep mailhost /etc/mail/*
/etc/mail/sendmail.mc:define(`MAIL_HUB', mailhost.convergys.com)dnl
/etc/mail/sendmail.mc:define(`SMART_HOST', smtp:mailhost.convergys.com)dnl
/etc/mail/submit.mc:FEATURE(`msp', `[mailhost.convergys.com]')dnl

An nslookup on mailhost shows:

[root@odccdds01 ~]# nslookup mailhost.convergys.com
Server: 155.90.250.207
Address: 155.90.250.207#53
mailhost.convergys.com canonical name = cvgmx1.convergys.com.
Name: cvgmx1.convergys.com
Address: 155.90.248.189

And mail is getting relayed to it for distribution as shiwn here:
May 19 04:17:24 odccdds01 sendmail[23063]: n4J8DNPd023063: to=mark.sylvia@convergys.com,michael.lense@convergys.com, delay=00:00:01, xdelay=00:00:01, mailer=esmtp, pri=102546, relay=cvgmx1in.convergys.com. [155.90.248.189], dsn=2.0.0, stat=Sent (Ok: queued as B4129150EF7E)

The issue is, whenever mail is sent to: CVGcpu@perf.dcd.convergys.com, the relay is changed to: trivium2.dcd.convergys.com instead of mailhost.convergys.com and there is no connection....

May 19 08:17:24 odccdds01 sendmail[26368]: n4J3wmcF013985: to=, ctladdr= (3/4), delay=08:18:36, xdelay=00:00:00, mailer=esmtp, pri=971290, relay=trivium2.dcd.convergys.com., dsn=4.0.0, stat=Deferred: Connection timed out with trivium2.dcd.convergys.com.

I don't see or understand where mailhost.convergys.com is being changed to trivium2.dcd.convergys.com ??? Any ideas as to what I may have setup wrong or where to check on this ?? I'm out of ideas...

[Steven E. Protter · Accepted solution]

Shalom,

A DNS server internally is providing a different answer for the server name than what is being provided to the target system.

You are best to change your smart host to the trivium2.dcd.convergys.com to get the mail through. You might look at the nslookup and dig/host command lookup for this second site.

DNS server inconsistency is probably the cause.

SEP

[MikeL_4]

I have always coded changes to just the /etc/mail/sendmail.mc and /etc/mail/submit.mc files. Then it was my uderstanding that when sendmail was started it re-created the /etc/mail/sendmail.cf and /etc/mail/submit.cf files.

To resolve this issue I codes the changes directly into the /etc/mail/sendmail.cf and /etc/mail/submit.cf files, restarted sendmail, and it is now working and sending mail as expected....