DNSless Sendmail
Fred Percynski
The following works for our customers who use UUCP and Sendmail.
It sounds like it should work for your problem. Add this to your
sendmail.cf file:
# Force Sendmail not to resolve host names
O ServiceSwitchFile=/etc/nsswitch.conf
Then create the file /etc/nsswitch.conf and populate it with:
# ServiceSwitchFile to tell Sendmail not to use DNS
hosts /etc/hosts
Hope it helps!
Fred
PS- Would you mind emailing me the ETRN script you wrote? I am
trying to learn more about ETRN. Thanks.
Mike Hawkins wrote:
>
> Hi people,
>
> I am attempting to confgure sendmail on SCO openserver enterprise to send
> mail to an ISP through a dial on demand modem connection. At this time,
> mail is sent everytime a user sends an email. If the email is addressed
> locally, ppp raises the modem connection. This I definitely want to stop
> happening. If the user sends mail externally then I want the mail to be
> held until a script (which I will write) raises the connection at which
> point sendmail should dump all externally addressed queued messages to the
> ISP server. Also, the script will send an ETRN queue message. I've tested
> the ETRN script and it works just fine. I'll schedule it with cron.
>
> I would love to disable DNS lookups by removing it altogether from the
> resolv.conf but I can't because other services (eg: squid proxy) must have
> DNS resolving available.
>
> Here is my sendmail config, hosts, resolv.conf and named.boot.
>
> Bind is set up to act as a cache DNS. Maybe it's not quite right but I
> think it works OK. Hosts has some redundant entries but apart from that it
> seems ok and resolv.conf seems OK to me as well. But I do know that
> sendmail.cf is probably out of kilter. If anyone can offer suggestions it
> would be much appreciated.
>
> The main issue is stopping the link from coming up when a local email is
> sent. That's a real pain and is costing the customer a fortune in local
> calls. Queueing externally addressed emails for a periodic send is next on
> my wish list.
>
> Here are the files,
>
> and regards from,
>
> Mike