netgroup(4)

NAME
     netgroup - list of NIS network groups

DESCRIPTION
     Netgroup defines network-wide groups, used for permission checking when
     doing remote mounts, remote logins, and remote shells.  For remote
     mounts, the information in netgroup is used to classify machines; for
     remote logins and remote shells, it is used to classify users.  Each line
     of the netgroup file defines a group and has the format

           groupname member1 member2 ....

     where memberi is either another group name, or a triple:

           (hostname, username, domainname)

           hostname:       The ``preferred'' name of the client host, the host
                           from which the rlogin(1C) or rsh(1C) command is
                           invoked.  Note that the preferred name is the first
                           name given to that host in the /etc/hosts file.
                           The second and later names are the aliases for that
                           preferred name.  The preferred name is commonly the
                           fully-qualified ``domain-style'' name.

           username:       This is the simple user name string.

           domainname:     This is the name of the domain of the server
                           system, not the client system.

     Any of three fields can be empty, in which case it signifies a wild card.
     Thus

           universal (,,)

     defines a group to which everyone belongs.  Field names that begin with
     something other than a letter, digit or underscore (such as ``-'') work
     in precisely the opposite fashion. For example, consider the following
     entries:

           justmachines  (analytica,-,sun)
           justpeople    (-,babbage,sun)

     The machine analytica belongs to the group justmachines in the domain
     sun, but no users belong to it.  Similarly, the user babbage belongs to
     the group justpeople in the domain sun, but no machines belong to it.

     The netgroup file is used solely to create NIS database maps.  This file
     is ignored if NIS is not running.
FILES
     /etc/netgroup

BUGS
     As in all NIS maps, the length limit of a netgroup is 1018 characters.
     Longer netgroups should be split.

SEE ALSO
     getnetgrent(3Y), innetgr(3Y), makedbm(1M), ypserv(1M)