stupid sendmail

[Les Mikesell]

Alexander Volovics wrote:
> As I have been using postfix a long time I have forgotten
> the little I knew about sendmail.
> But I thought it would have been configured by default to allow
> the mail from (ana)cron to work without problems and complaints.
> 
> On a laptop on which I have been trying out F8 test3 I decided to
> not use my standard postfix/mutt/fetchmail/procmail setup but make
> do with claws-mail instead. 
> So I just left sendmail (not needing it) with the default install
> configuration.
> 
> To my surprise I see constant error messages when getting mail from
> Mail Delivery Subsystem <MAILER-DAEMON at localhost.localdomain>
> Namely:
> - Tried to mail output of jon 'cron daily', but mailer proces
>   (usr/bin/sendmail) exited with status 65
> - The following addresses had permanent fatal errors -----
>   root
>     (reason: 553 5.5.4 <root at localhost.localdomain>... Real domain name
>      required for sender address) (expanded from: root)
> - relay localhost (127.0.0.1) may be forged
> 
> Eventually I do get the mail in /var/spool/mail/user and claws-mail
> picks it up (again with a summary of the errors).
> 
> Wouldn't it be neater to configure sendmail to perform these simple
> duties without these hiccups.
> I expect that if /etc/aliases is not changed to deliver root's mail to
> user the user might never get any cron mail and newbies might be
> confused on seeing possible error messages when mail is delivered
> to root.
> 
> A further irritation occurs when using 'mail' to send messages from
> user to user. The do not arrive at /var/spool/mail/user but are dropped
> as "dead.letter" in the users home directory

Sendmail is an internet mailer and comes configured to follow internet 
rules.  It is infinitely configurable, though, so if you want it to do 
something else you probably can.

> Is this mentioned somewhere. It should be.

Read through the comments in /etc/mail/sendmail.mc. That's a small 
subset of what you can change, but it's probably enough.  After making a 
change there, do a 'service sendmail restart' to rebuild sendmail.cf and 
pick up the changes.

-- 
   Les Mikesell
    lesmikesell at gmail.com