More on Masquerading

[Harry Putnam]

Ow Mun Heng <Ow.Mun.Heng at wdc.com> writes:

[...]

>> >From another thread I've learned that masquerading doesn't work as I
>> thought it did but for years now I've been masquerading what ever
>> machines I have at home as `newsguy.com'.  I thought I'd learned a way
>> of using the `genericstable' to do something similar and not need to
>> masquerade.
> What exactly does genericstable do? (Sorry, writing this mail off-line)

Sorry Mun, I'm finding out I don't know either.  I believe my usage is
supposed to rewrite my outgoing mail From so that the real name of my
host (reader.local.net0 as in reader at reader.local.net) is rewritten to
be reader at newsguy.com and in fact it does do that.  Further along you
ask what the contents of my genericstable is supposed to do.  ... well
it is supposed to do what I lay out above and it does.  The problem is
I don't really understand what effect that has on how my mail is
received on the internet.

>> sendmails outgoing activity required a resolvable host as source IP to
>> avoid bouncing.  I thought by setting some genericstable vars I could
>> make it appear to be a resolvable host name.

> But it isn't right? newsguy.com isn't a valid Domain Name is it??

Yes, its just not my domain name.

> I'm not sure if your solution is a viable solution to my problem.

> My Problem.
>
> @work = mails must be sent out using the corp exhange server (smart host
> feature _must_ be implemented via sendmail.mc)
>
> @home = mails are sent out w/o using smart host. Meaning, I have to
> actively re-compile sendmail.mc each time between office and home to
> send out emails. Cause @home, mails gets relayed directly to the
> receipient's MX. 

I'm not sure either.. sorry.  But I can think of a partial solution.
There is really no need to actually recompile sendmail.cf each time.
It would suffice to just hand edit the Smart_host entry (in
/etc/sendmail.cf not sendmail.mc), and restart sendmail daemon.

This could be fairly easy to script and automate, but is really a poor
solution in that it doesn't answer the underlaying problem.

>> It is not an internet FQDN, just my own made up domain for my local
>> lan.  Therefore will never be resovable by dns lookups.

> Just as I thought. And what/how does this affect mail sending?

I thought I new but am finding out my assumptions were incorrect.
I can only say for sure that by including two masquerading type
entries in sendmail.mc my mail works.  Otherwise it does not.

  MASQUERADE_AS(`whizbang.net')dnl
  FEATURE(masquerade_envelope)dnl
The idea that it needed to be set to `newsguy.com' I have found to be
completely mistaken.  It seems it can be set to anything.  Even
fantastic like above.  But somehow this makes it work.

[...]

>> And to /etc/mail/genericstable:
>>    reader               reader at newsguy.com

> What does this achieve?  I don't see a genericstable in my
>  /etc/mail/ directory

It's supposed to achieve what I laid out earlier.
genericstable isn't there by default it is user created.

>
> What's data format error? And I see that your relay is =
> smtp.newsguy.com, which resolves to your Inet Public IP.
>
> For my case, it gets relayed to the localhost (127.0.0.1)'s smtp. which
> then hands it over to sendmail to contact the MX.

The error I posted is from my local smtp process not newsguy. It just
tells us that my relay is smtp.newsguy.com.
That error can mean many things I think.  I don't know what it means
in this case.  I've always thought it meant that newsguys smtp machine
didn't like my From or sender address.

I suspect your problem could be solved with genericstable but I don't
know how to do it ...sorry.

You'd probably do better by posting a description of your problem on
comp.mail.sendmail newsgroup  There are good answers there sometimes.