# # sendmail domain masquerading
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sendmail domain masquerading

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© April 2005 dhart

Author: dhart
Date: Tue Apr 12 16:49:48 2005
Subject: sendmail domain masquerading

Mail from host 'redhat' is being relayed through smtp.conservent.com, which rejects the email since it has no reverse DNS path to redhat.alliedstorage.com. I don't want to make a record for redhat.alliedstorage.net. I do want to make email from redhat.alliedstorage.com appear to come from alliedstorage.com so that smtp.conservent.com won't reject it.

Domain Masquerading sounded like just the ticket, too bad I can't make it work. Here are the pertinent sections (afaik):


I restarted sendmail and tested with no luck. Ideas?

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Tue Apr 12 19:03:42 2005: 331   TonyLawrence

Is there a reason you can't use the mc files to generate your conf? Did you edit the right file (sendmail runs as two separate processes now - with separate config files)?

Tue Apr 12 22:20:32 2005: 334   dhart

At this site (RH EL3)

# m4 /etc/mail/sendmail.mc > /etc/sendmail.cf
/etc/mail/sendmail.mc:10: m4: Cannot open /usr/share/sendmail-cf/m4/cf.m4: No such file or directory

which is why I tried editing sendmail.cf directly. There is NO cd.m4 on this system

After some thought I realized that the sendmail-cf package had never been installed on this machine. I used up2date sendmail-cf to install it, edited the bits in sendmail.mc that seemed reasonable, typed m4 /etc/mail/sendmail.mc > /etc/mail/sendmail.cf stopped and started sendmail and I was masquerading, something no amount of fiddling in sendmail.cf seemed to accomplish.

Now on to the smart host bit. I defined it as define(`SMART_HOST', `smtp.conservent.com'), ran m4, stopped & started sendmail et voila!

Tue Apr 12 22:35:29 2005: 335   anonymous

Now if you look at your cf carefully, you'll see what the mc accomplished, and be able to do it manually if you ever have to.. not that you'd want to, its easier with m4.

Mon Jun 4 08:58:22 2007: 3017   Abhilash

I am not an expert but just trying to give my opinion.

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

/etc/mail/sendmail.mc:10: m4: Cannot open /usr/share/sendmail-cf/m4/cf.m4:
No such file or directory

This error is due to a line in the sendmail.mc file. The line is


This line is very important for the proper working.


Thank you.

Abhilash V Nair
Slashome technologies Private Limited.">

Fri Aug 17 11:10:46 2007: 3080   anonymous

Hi ..
This is Arun sasi V Network solutions an IBM company INDIA
This errors simply means you do not have the sendmail-cf package installed. You can use up2date or manually

ph : +919986141006

Mon Mar 24 15:13:57 2008: 3885   pradip

ur suggestion resloved my issue. thanks a bunch.

Mon Mar 24 15:17:58 2008: 3886   pradip

ur suggestion resloved my issue. thanks a bunch.

Mon Jul 6 07:31:11 2009: 6614   achyot

Thanx for the help...


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