On Wed, 20 Mar 2001, Mike Nielsen wrote:

> Hi there, a while back I posted a question about my attempt to configure my
> sendmail box to relay/spool mail for another domain.
> 
> I was helped along by simply adding the domains (Not mine, the ones I want to
> spool for) to  /etc/mail/relay-domains
>
> This seems to work for allowing these domains to use my mail server as a
> relay and to accept the mail and pass it on.
> 
> The problem:  When I unplug the other mail server and send an article of mail
> out the message queue's up in my server as I expect it to  (I am listed as a
> secondary MX for their domain)    15 minutes or so later the mail will bounce
> back saying the message could not be delivered with one of two errors.  1 (MX
> points back to myself)  (The sendmail server is also my DNS server)  Or The
> message could not be delivered.
>
> Is this what is supposed to happen by default?

 If you set it up wrong, yes.
 I'm not ripping on you with that.  It took me a few weeks to figure the
trick out.  It's only vaguely documented, and even that's hard to find.
 Do you have mailertable support in your sendmail.cf file?  (As Bob Tanner
said, don't edit sendmail.cf -- it's very messy.  Rebuild the
configuration from an .mc file.  For mailertable, add 
"FEATURE(`mailertable')dnl" to your .mc file.)
 Anyway, mailertable's format is usually like this:

something.com		smtp:mail1.something.com

 However, if you're a higher-numbered MX for something.com, and mail1 is
down when your server receives the mail, you're going to get that stupid
error.  (Like I did 100 times.)  The trick is, if you surround the
hostname you're forwarding to with brackets, it'll ignore the MX records
and do whatever you tell it to.

something.com		smtp:[mail1.something.com]

 As I said, it's a poorly documented workaround.  There's one reference to
it in the cf/README file (around line 2334, for 8.11.1 anyway), but aside
from that, I couldn't find anything mentioning it.

> If I want my server to hang onto a given piece of email for 10 days or so and
> continue to try to deliver, is there something else I need to set.  I find
> the sendmail.cf help files a little vague on this  (Yes I know Sendmail is a
> nightmare to configure...)

 Usually sendmail will hold onto an email for 4 or 5 days before it dumps
it. I'm not aware of a way to change that.

 Hope this helps.

     Jima