[vox-tech] Sendmail trouble

[Charles Polisher]

On Wed, Jan 01, 2003 at 05:11:11AM +0530, karthikeyan.balasubramanian wrote:
> Hi All,
>   Wish you all a very Happy New Year.
>   I am having problem with my sendmail.  Somehow mails are not going outside.  
>   My Environment is Redhat Linux 7.3.
>   What are all the files (logs) i need to check to debug. 
>   Please let me know if there is any easy to understand tutorial to sendmail which 
>   could help solve my problem.
>   Have a great day.
> Karthikeyan B

O'Reilly's book on sendmail (Costales & Allman) is one of the
best-written technical books in my collection. It's right 
around 1,000 pages, but don't let that intimidate you -- just
read Part I (Tutorial) and you can use the remainder of the
book as a comprehensive cross-reference.

/var/log/mail may be useful.

The main sendmail file is /etc/sendmail.conf. It's not too
likely to mutate on its own, unless you've just upgraded
or such.

Does the mail get delivered when you (as root) run 
"sendmail -q" ?  If so, sendmail isn't getting
asked to send mail automatically.

If you run:  "sendmail -d0.4" you get a brief dump
of some of the key internal settings. There are nearly
200 available debug settings for sendmail, and they
are extensively cross-referenced and cleary described 
in chapter 37. You can watch sendmail process the mail
in incredible detail with the right mix of debug opts.
Eg., sendmail -q -d<opt1>,<opt2>,...<optn>
Some useful debug option #s:
11.1   trace delivery
27.1   aliasing
31.2   header processing
35.9   internal macro def's
35.24  macro expansion
37.1   option setting
40.4   display file lines as they are read
99.100 prevent daemon from backgrounding

Expect to see flames from people who don't like sendmail.
It has an undeserved reputation for being hard to configure
and full of security holes. Last time I looked, the vast
majority of e-mail servers were running sendmail. This
makes it a high-profile target for black-hats, and the 
sheer number of installations guarantees a steady flow of
chatter regarding config issues. Don't be fooled! sendmail
rocks!