Sendmail Masquerading and root mails

[MrFollies]

I have a situation that I've come accross from time to time that I have never found a good fix for.

Sometimes I'll install a freebsd box at a site with private addresses (RFC 1918). Most of the time these sites also have local DNS setups.

I'll take my home network as an example. My FreeBSD box (7.2) does:
- File serving
- PPP/Routing/NATd for the local network
- WWW
- Local DNS

Nothing special.
The network is a 192.168 network and the local domain is .lan

The problem is when I try to forward periodic output to my real email address. My email box see's the EHLO from beastie.lan and rejects the message based on the fact that root@beastie.lan is an unroutable address.

There are a few solutions I've used in the past.
- Replace sendmail with exim and configure the SMTP domain.
- Put beastie.lan in my email servers hosts file.

Neither of these are what I am looking for. I'd like to make sendmail re-write all outgoing emails (envelope as well as message) as *@some.real.domain instead of *@beastie.lan.

I have a simple sendmail submit setup. (sendmail=no in rc.conf)

I've added the following to the default sendmail mc file:

MASQUERADE_AS(`mypublicdomain.com')dnl
FEATURE(masquerade_envelope)dnl
MASQUERADE_DOMAIN(beasie.lan)dnl

Recompiled the cf files and restarted sendmail.

Here is the kicker. If I log in as a normal user it masquerades just fine.

If I simply "su -" to root, the masquerading works fine and the mail is sent as the original logged in user.

But if I log in as root via the console then it does not alter the messages.

Apart from ditching sendmail for another MTA, does anyone know how I might coerce sendmail into rewriting root's messages as well?

 

[aragon]

You might like mail/ssmtp. It is a very small, simple MTA that would replace sendmail, but it's simplicity means it's trivial to setup. All it does is allow a unix system to funnel local mail to an SMTP relay that you configure, and it supports domain rewriting.

 

[MrFollies]

You might like mail/ssmtp. It is a very small, simple MTA that would replace sendmail, but it's simplicity means it's trivial to setup. All it does is allow a unix system to funnel local mail to an SMTP relay that you configure, and it supports domain rewriting.

Thanks for the tip. I think I could probably configure sendmail to do this via it's smart host feature. I could also fix it, by using exim or postfix. But that's kinda not the point. I'd really like to know what I need to to to make this work with the standard sendmail setup so I can just add it to my standard install procedure. Plus I'd learn something about sendmail.

 

[DutchDaemon]

Not sure that what you want can be done:

There are always users that need to be "exposed" -- that is, their
internal site name should be displayed instead of the masquerade name.
Root is an example (which has been "exposed" by default prior to 8.10).

Note that this concerns 'true root' (which you get from a straight console login, and which the local root user has when handling system/cron mail), not 'acquired root' (su or su -, which retains your 'original login identity' in the background).