1 YPFILES(4)              File Formats and Configurations             YPFILES(4)
   2 
   3 
   4 
   5 NAME
   6        ypfiles - Network Information Service Version 2, formerly known as YP
   7 
   8 DESCRIPTION
   9        The NIS network information service uses a distributed, replicated
  10        database of dbm files , in ASCII form, that are contained in the
  11        /var/yp directory hierarchy on each NIS server.
  12 
  13 
  14        A dbm database served by the NIS server is called a NIS map. A NIS
  15        domain is a subdirectory of /var/yp that contains a set of NIS maps on
  16        each NIS server.
  17 
  18 
  19        Standard nicknames are defined in the file /var/yp/nicknames. These
  20        names can be used in place of the full map name in the ypmatch and
  21        ypcat commands. Use the command ypwhich -x to display the current set
  22        of nicknames. Use the command ypwhich -m to display all the available
  23        maps. Each line of the nickname file contains two fields separated by
  24        white space. The first field is the nickname, and the second field is
  25        the name of the map that it expands to. The nickname cannot contain a
  26        ".".
  27 
  28    NIS to LDAP (N2L)
  29        If the /var/yp/NISLDAPmapping configuration file is present, the NIS
  30        server operates in NIS to LDAP (N2L) mode. In this mode, NIS maps are
  31        stored in a new set of DBM files, prepended by the LDAP_ prefix, at
  32        /var/yp/domainname. These files are used as a cache backed by
  33        information from an LDAP server. Additional DBM files are created in
  34        the same directory to hold the cache's TTL values.
  35 
  36 
  37        N2L mode enables NIS clients to be supported in an LDAP environment.
  38 
  39 
  40        In N2L mode, the old style DBM files, NIS source files, and the
  41        ypmake(1M) utility have to role. They are retained to enable easy
  42        conversion back to the traditional mode, if required.
  43 
  44    Converting from N2L to Traditional NIS
  45        When NIS is operating in N2L mode, it uses a new set of NIS maps with
  46        an LDAP_ prefix, based on the contents of the LDAP DIT. The NIS source
  47        files are unused and become out of date. If you wish to convert back to
  48        the traditional NIS mode, the N2L configuration file should be deleted.
  49        The system will then return to using the standard map files.
  50        Optionally, the N2L mode map files, /var/yp/*/LDAP_* can also be
  51        deleted.
  52 
  53 
  54        If you want to run the system in traditional mode with information
  55        based on the DIT, then the NIS source files must be regenerated based
  56        on the N2L maps. To regenerate the NIS source files based on the N2L
  57        maps, run ypmap2src(1M).
  58 
  59 FILES
  60        /var/yp
  61 
  62            Directory containing NIS configuration files.
  63 
  64 
  65        /var/yp/binding
  66 
  67            Stores the information required to bind the NIS client to the NIS
  68            server.
  69 
  70 
  71        /var/yp/binding/ypdomain/ypservers
  72 
  73            Contains the servers to which the NIS client is allowed to bind.
  74 
  75 
  76        /var/yp/Makefile
  77 
  78            Builds the NIS ndbm databases.
  79 
  80 
  81        /var/yp/nicknames
  82 
  83            Nicknames file.
  84 
  85 
  86        /var/yp/securenets
  87 
  88            Defines the hosts and networks that are granted access to
  89            information in the served domain. This file is read at startup time
  90            by ypserv and ypxfrd.
  91 
  92 
  93        /var/yp/ypdomain
  94 
  95            Directory containing ndbm databases.
  96 
  97 
  98        /var/yp/NISLDAPmapping
  99 
 100            NIS to LDAP configuration file
 101 
 102 
 103        /var/yp/*/LDAP_*
 104 
 105            NIS to LDAP mode map files
 106 
 107 
 108 SEE ALSO
 109        ldap(1), makedbm(1M), ypbind(1M), ypinit(1M), ypmake(1M),
 110        ypmap2src(1M), ypserv(1M), ypxfrd(1M), ndbm(3C), ypclnt(3NSL)
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 114                                February 25, 2017                    YPFILES(4)