Name
nis
Synopsis
Sun
Microsystems offers a network information service called NIS. It
provides the ability to look up various kinds of information in
network databases. The nis
type allows you to
access that network information by way of rules in rule sets. You
declare an nis
database-map type like this:
Kname nis nismap
Here, name
is the identifier that you will
later use in rule sets. The nismap
is any
NIS database map that defaults to mail.aliases.
Lookups will occur in the default NIS domain. If you wish to specify
some other domain, you can append an @
character
and the domain name to the nismap:
Kname nis nismap @ domain
To illustrate, consider the need to look up the name of the central mail server for your department. If such a database map were called mailservers, you could use the following configuration file line to look up your domain in that database map:
Kmailservers nis -o mailservers ... R $* <@ $+ > $* $: $1<@$2>$3 <$(mailservers $2 $)> R $* <@ $+ > $* <$+> $#smtp $@ $4 $: $1 < @ $2 > $3 ...
Here, we look up the host part of an address ($2
)
in the mailservers
NIS database map. The
-o
makes the existence of the database map
optional. If the host part is found, it is rewritten to be the name
of the mail server for that host. In the last rule we forward the
original address to that server.
Without the -o
, the nonexistence of a database map
will cause this error to be logged:
Cannot bind to map name in domain domain:reason here
If NIS is not running or if sendmail cannot ...
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