ypservers(4)                                                   ypservers(4)

NAME
     ypservers - determine NIS server names

DESCRIPTION
     If a program requires information from a NIS file, it asks ypbind [see
     ypserv(1M)] for the name of a NIS server. The server name that ypbind
     passes to the program depends on entries in the file
     /var/yp/binding/domainname/ypservers.

     If this file does not exist on a client computer, the ypbind daemon
     finds a NIS server ready for the domain domainname by issuing a broad-
     cast call. The first server to respond is accepted as the NIS server.

     If the file /var/yp/binding/domainname/ypservers is automatically
     adapted to match the NIS file ypservers owing to the entry
     AUTOBINDING=yes in the file /etc/default/inet, it will have a plus
     entry first (see below), followed by a list of host names. These host
     names are taken from the NIS file ypservers [see inet(4)].

     The entries in the file have the following structure:

          +[.nettype]    # referred to below as "plus entry"

          *[.nettype]    # referred to below as "asterisk entry"

          Hostname       names of NIS servers

     The entries can be typed in one line one after the other separated by
     blanks or tabs, or line by line (separator character: new line).

     Plus entry
          This entry produces a broadcast call to find a NIS server in the
          set domain. However, ypbind accepts a responding server only when
          its host name is contained in the list of host names following
          "+".

          The following is the basic structure of the broadcast call:

          rpcbroadcast(YPPROG, YPVERS, YPPROCDOMAINNONACK, ... nettype)

     Asterisk entry
          Like the plus entry, this entry produces a broadcast call to find
          a NIS server for the set domain. However, in this case any server
          which responds will be accepted.

     Hostname
          If a list of host names is entered in the file
          /var/yp/binding/domainname/ypservers and there is no plus entry
          before this list, ypbind reads the first entry and tries to con-
          nect to this host. If the server does not respond, the attempt is
          repeated with the next entry, and so on until the list of host
          names is exhausted.



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ypservers(4)                                                   ypservers(4)

EXAMPLES
     1)  The file /var/yp/binding/xsmuc/ypservers has the following
         entries:

         +
         boston
         chicago
         seattle

         The ypbind daemon issues a broadcast call. If, for example, the
         host chicago is the first NIS server to respond in domain xsmuc,
         it is accepted. If, on the other hand, the host primus responds,
         it will not be accepted as NIS server.

     2)  The file /var/yp/binding/xsmuc/ypservers has the following
         entries:

         boston
         chicago
         seattle
         *

         The daemon tries in turn to connect to the computers boston, chi-
         cago and seattle. If none of these computers responds, a broadcast
         call is issued (owing to the asterisk entry).

FILES
     /etc/default/inet

SEE ALSO
     ypserv(1M), inet(4).























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