xref: /freebsd/usr.sbin/ypbind/ypbind.8 (revision 5ebc7e6281887681c3a348a5a4c902e262ccd656)
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32.\"	$Id: ypbind.8,v 1.1 1995/04/09 21:59:06 wpaul Exp $
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34.Dd April 9, 1995
35.Dt YPBIND 8
36.Os
37.Sh NAME
38.Nm ypbind
39.Nd "NIS domain binding daemon"
40.Sh SYNOPSIS
41.Nm ypbind
42.Op Fl ypset
43.Op Fl ypsetme
44.Op Fl s
45.Sh DESCRIPTION
46.Nm ypbind
47is the process that maintains NIS binding information. At startup,
48it searches for an NIS server responsible for serving the system's
49default domain (as set by the
50.Xr domainname 1
51command) using network broadcasts.
52Once it receives a reply,
53it will store the address of the server and other
54information in a special file located in
55.Pa /var/yp/binding .
56The NIS routines in the standard C library can then use this file
57when processing NIS requests. There may be several such files
58since it is possible for an NIS client to be bound to more than
59one domain.
60.Pp
61After a binding has been established,
62.Nm ypbind
63will send DOMAIN_NONACK requests to the NIS server at one minute
64intervals. If it fails to receive a reply to one of these requests
65.Nm ypbind
66assumes that the server is no longer running and resumes its network
67broadcasts until another binding is established.
68.Nm ypbind
69will also log warning messages using the syslog(3) facility each time
70it detects that a server has stopped responding, as well as when it
71has bound to a new server.
72.Pp
73.Sh OPTIONS
74The following options are supported by
75.Nm ypbind :
76.Bl -tag -width flag
77.It Fl ypset
78It is possible to force
79.Nm ypbind
80to bind to a particular NIS server host for a given domain by using the
81.Xr ypset 8
82command. However,
83.Nm ypbind
84refuses YPBINDPROC_SETDOM requests by default since it has no way of
85knowing exactly who is sending them. Using the
86.Fl ypset
87flag causes
88.Nm ypbind
89to accept YPBINDPROC_SETDOM requests from any host. This option should only
90be used for diagnostic purposes and only for limited periods since allowing
91arbitrary users to reset the binding of an NIS client poses a severe
92security risk.
93.It Fl ypsetme
94This is similar to the
95.Fl ypset
96flag, except that it only permits YPBINDPROC_SETDOM requests to be processed
97if they originated from the local host.
98.It Fl s
99The
100.Fl s
101flag causes
102.Nm ypbind
103to run in secure mode: it will refuse to bind to any NIS server
104that is not running as root (i.e. that is not using privileged
105TCP ports).
106.Sh NOTES
107.Nm ypbind
108will not make continuous attempts to keep secondary domains bound.
109If a server for a second dary domain fails to respond to a ping,
110.Nm ypbind
111will broadcast for a new server only once before giving up. If a
112client program attempts to reference the unbound domain, ypbind will
113try broadcasting again. By contrast,
114.Nm ypbind
115will automatically maintain a binding for the default domain whether
116client programs reference it ot not.
117.Sh FILES
118.Bl -tag -width Pa -compact
119.It Pa /var/yp/binding/[domainname].[version]
120The files used to hold binding information for each NIS domain.
121.El
122.Sh SEE ALSO
123.Xr syslog 3 ,
124.Xr domainname 1 ,
125.Xr ypserv 8 ,
126.Xr ypset 8 ,
127.Xr yp 8
128.Sh AUTHOR
129Theo de Raadt <deraadt@fsa.ca>
130