1ypbind(1M) System Administration Commands ypbind(1M)
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6 ypbind - NIS binder process
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9 /usr/lib/netsvc/yp/ypbind [-broadcast | -ypset | -ypsetme]
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13 NIS provides a simple network lookup service consisting of databases
14 and processes. The databases are stored at the machine that runs an NIS
15 server process. The programmatic interface to NIS is described in
16 ypclnt(3NSL). Administrative tools are described in ypinit(1M),
17 ypwhich(1), and ypset(1M). Tools to see the contents of NIS maps are
18 described in ypcat(1), and ypmatch(1).
19 ypbind is a daemon process that is activated at system startup time
22 from the svc:/network/nis/client:default service. By default, it is
23 invoked as ypbind -broadcast. ypbind runs on all client machines that
24 are set up to use NIS. See sysidtool(1M). The function of ypbind is to
25 remember information that lets all NIS client processes on a node com‐
26 municate with some NIS server process. ypbind must run on every machine
27 which has NIS client processes. The NIS server may or may not be run‐
28 ning on the same node, but must be running somewhere on the network. If
29 the NIS server is a NIS+ server in NIS (YP) compatibility mode, see the
30 NOTES section of the ypfiles(4)man page for more information.
31 The information ypbind remembers is called a binding — the association
34 of a domain name with a NIS server. The process of binding is driven by
35 client requests. As a request for an unbound domain comes in, if
36 started with the -broadcast option, the ypbind process broadcasts on
37 the net trying to find an NIS server, either a ypserv process serving
38 the domain or an rpc.nisd process in "YP-compatibility mode" serving
39 NIS+ directory with name the same as (case sensitive) the domain in the
40 client request. Since the binding is established by broadcasting,
41 there must be at least one NIS server on the net. If started without
42 the -broadcast option, ypbind process steps through the list of NIS
43 servers that was created by ypinit -c for the requested domain. There
44 must be an NIS server process on at least one of the hosts in the NIS
45 servers file. It is recommended that you list each of these NIS servers
46 by name and numeric IP address in /etc/hosts. Though the practice is
47 not recommended, NIS allows you to list servers by numeric address
48 only, bypassing /etc/hosts. In such a configuration, ypwhich(1) returns
49 a numeric address instead of a name.
50 Once a domain is bound by ypbind, that same binding is given to every
53 client process on the node. The ypbind process on the local node or a
54 remote node may be queried for the binding of a particular domain by
55 using the ypwhich(1) command.
56 If ypbind is unable to speak to the NIS server process it is bound to,
59 it marks the domain as unbound, tells the client process that the
60 domain is unbound, and tries to bind the domain once again. Requests
61 received for an unbound domain will wait until the requested domain is
62 bound. In general, a bound domain is marked as unbound when the node
63 running the NIS server crashes or gets overloaded. In such a case,
64 ypbind will try to bind to another NIS server using the process
65 described above.ypbind also accepts requests to set its binding for a
66 particular domain. The request is usually generated by the ypset(1M)
67 command. In order for ypset to work, ypbind must have been invoked with
68 flags -ypset or -ypsetme.
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71 -broadcast
72 Send a broadcast datagram using UDP/IP that requests the informa‐
74 tion needed to bind to a specific NIS server. This option is analo‐
75 gous to ypbind with no options in earlier Sun releases and is rec‐
76 ommended for ease of use.
77 -ypset
80 Allow users from any remote machine to change the binding by means
82 of the ypset command. By default, no one can change the binding.
83 This option is insecure.
84 -ypsetme
87 Only allow root on the local machine to change the binding to a
89 desired server by means of the ypset command. ypbind can verify
90 the caller is indeed a root user by accepting such requests only on
91 the loopback transport. By default, no external process can change
92 the binding.
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96 /var/yp/binding/ypdomain/ypservers
97 Lists the servers to which the NIS client is allowed to bind.
99 /etc/inet/hosts
102 File in which it is recommended that NIS servers be listed.
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107 See attributes(5) for descriptions of the following attributes:
108 ┌─────────────────────────────┬─────────────────────────────┐
113 │ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
114 ├─────────────────────────────┼─────────────────────────────┤
115 │Availability │SUNWnisu │
116 └─────────────────────────────┴─────────────────────────────┘
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119 svcs(1), ypcat(1), ypmatch(1), ypwhich(1), ifconfig(1M), rpc.nisd(1M),
120 svcadm(1M), ypinit(1M), ypset(1M), ypclnt(3NSL), hosts(4), ypfiles(4),
121 attributes(5), smf(5)
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124 ypbind supports multiple domains. The ypbind process can maintain
125 bindings to several domains and their servers, the default domain is
126 the one specified by the domainname(1M) command at startup time.
127 The -broadcast option works only on the UDP transport. It is insecure
130 since it trusts "any" machine on the net that responds to the broadcast
131 request and poses itself as an NIS server.
132 The ypbind service is managed by the service management facility,
135 smf(5), under the service identifier:
136 svc:/network/nis/client:default
138 Administrative actions on this service, such as enabling, disabling, or
143 requesting restart, can be performed using svcadm(1M). The service's
144 status can be queried using the svcs(1) command.
145SunOS 5.11 20 Dec 2007 ypbind(1M)