+If you have FEATURE(nocanonify), you may need to omit the dots after
+the $m. If you are running a local DNS inside your domain which is
+not otherwise connected to the outside world, you probably want to
+use:
+
+ define(`SMART_HOST', smtp:fire.wall.com)
+ LOCAL_NET_CONFIG
+ R$* < @ $* . > $* $#smtp $@ $2. $: $1 < @ $2. > $3
+
+That is, send directly only to things you found in your DNS lookup;
+anything else goes through SMART_HOST.
+
+If you are not running DNS at all, it is important to use
+FEATURE(nodns) to avoid having sendmail queue everything waiting
+for the name server to come up.
+
+
++-----------+
+| WHO AM I? |
++-----------+
+
+Normally, the $j macro is automatically defined to be your fully
+qualified domain name (FQDN). Sendmail does this by getting your
+host name using gethostname and then calling gethostbyname on the
+result. For example, in some environments gethostname returns
+only the root of the host name (such as "foo"); gethostbyname is
+supposed to return the FQDN ("foo.bar.com"). In some (fairly rare)
+cases, gethostbyname may fail to return the FQDN. In this case
+you MUST define confDOMAIN_NAME to be your fully qualified domain
+name. This is usually done using:
+
+ Dmbar.com
+ define(`confDOMAIN_NAME', `$w.$m')dnl
+
+
++--------------------+
+| USING MAILERTABLES |
++--------------------+
+
+To use FEATURE(mailertable), you will have to create an external
+database containing the routing information for various domains.
+For example, a mailertable file in text format might be:
+
+ .my.domain xnet:%1.my.domain
+ uuhost1.my.domain suucp:uuhost1
+ .bitnet smtp:relay.bit.net
+
+This should normally be stored in /etc/mailertable. The actual
+database version of the mailertable is built using:
+
+ makemap hash /etc/mailertable.db < /etc/mailertable
+
+The semantics are simple. Any LHS entry that does not begin with
+a dot matches the full host name indicated. LHS entries beginning
+with a dot match anything ending with that domain name -- that is,
+they can be thought of as having a leading "*" wildcard. Matching
+is done in order of most-to-least qualified -- for example, even
+though ".my.domain" is listed first in the above example, an entry
+of "uuhost1.my.domain" will match the second entry since it is
+more explicit.
+
+The RHS should always be a "mailer:host" pair. The mailer is the
+configuration name of a mailer (that is, an `M' line in the
+sendmail.cf file). The "host" will be the hostname passed to
+that mailer. In domain-based matches (that is, those with leading
+dots) the "%1" may be used to interpolate the wildcarded part of
+the host name. For example, the first line above sends everything
+addressed to "anything.my.domain" to that same host name, but using
+the (presumably experimental) xnet mailer.
+
+
++--------------------------------+
+| USING USERDB TO MAP FULL NAMES |
++--------------------------------+
+
+The user database was not originally intended for mapping full names
+to login names (e.g., Eric.Allman => eric), but some people are using
+it that way. (I would recommend that you set up aliases for this
+purpose instead -- since you can specify multiple alias files, this
+is fairly easy.) The intent was to locate the default maildrop at
+a site, but allow you to override this by sending to a specific host.
+
+If you decide to set up the user database in this fashion, it is
+imperative that you also specify FEATURE(notsticky) -- otherwise,
+e-mail sent to Full.Name@local.host.name will be rejected.
+
+To build the internal form of the user databae, use:
+
+ makemap btree /usr/data/base.db < /usr/data/base.txt