What is dnl in sendmail mc

For every user that needs to have mail delivered to cyrus instead of locally, add their user id to the class definition line. This list should be single-space separated. This inelegant method must be administered every time you rebuild the sendmail. Configuration Next. With this feature, all addresses that are locally delivered will be fully qualified. It is safe and recommended to set this feature for security reasons.

With this feature you can use procmail as a Sendmail delivery agent. This m4 macro enables the access database feature. With this feature you have the ability through the access db to allow or refuse to accept mail from specified domains.

Usually this feature must be available only in a Central Mail Hub server. This m4 macro enables the ability to block incoming mail for certain recipient usernames, hostnames, or addresses. With this feature you can, for example, block incoming mail to user nobody , host foo.

This m4 macro enables Sendmail to reject mail from any site in the Realtime Blackhole List database rbl. This m4 macro enables the use of local, smtp, and procmail as delivery agents in Sendmail by default, delivery agents are not automatically declared. With this feature, you can specify which ones you want to support and which ones to ignore. Sometimes, a domain with which you wish to continue communications may end up in the RBL list.

In this case, Sendmail allows you to override these domains to allow their e-mail to be received. Anything that remains in the output, of course, will either be sendmail configuration, or a comment that begins with , which will be copied as-is into sendmail. Anything beginning with and not deleted above will make it into sendmail. In your example, someone meant for all of the commented features to be removed from sendmail.

DNL means "delete through newline" which really means "ignore everything after 'dnl' until the next line". The default configuration allows connections only from localhost. If you want Sendmail to work as a server for other computers on your network, look for the following line in the sendmail. An open relay is a mail server that's configured to allow anyone to use it as a relay for sending mail. In short, an open relay sends mail when neither the sender nor the recipient is a local user.

Spammers love open relays because they can use them to obscure the true origin of their junk e-mail. As a result, open relays are a major contributor to the Internet spam problem. Fortunately, the default configuration for the current version of Sendmail 8. As a result, you have to go out of your way to become an open relay with Sendmail. In fact, you'll have to look up the lines you'd need to add to sendmail. Then, add a line for each domain you want to allow relaying for.