ypbind(1M)						  System Administration Commands						ypbind(1M)

NAME

       ypbind - NIS binder process

SYNOPSIS

       /usr/lib/netsvc/yp/ypbind [-broadcast | -ypset | -ypsetme]

DESCRIPTION

       NIS  provides  a  simple network lookup service consisting of databases and processes. The databases are stored at the machine that runs an
       NIS server process. The programmatic interface to NIS is described in ypclnt(3NSL).  Administrative  tools  are	described  in  ypinit(1M),
       ypwhich(1), and ypset(1M). Tools to see the contents of NIS maps are described in ypcat(1), and ypmatch(1).

       ypbind  is  a  daemon  process that is activated at system startup time from the svc:/network/nis/client:default service. By default, it is
       invoked as ypbind -broadcast. ypbind runs on all client machines that are set up to use NIS. See sysidtool(1M). The function of	ypbind	is
       to  remember  information  that	lets all NIS client processes on a node communicate with some NIS server process. ypbind must run on every
       machine which has NIS client processes. The NIS server may or may not be running on the same node, but must be  running	somewhere  on  the
       network. If the NIS server is a NIS+ server in NIS (YP) compatibility mode, see the NOTES section of the ypfiles(4)man page for more infor-
       mation.

       The information ypbind remembers is called a binding -- the association of a domain name with a NIS  server.  The  process  of  binding	is
       driven by client requests.  As a request for  an unbound domain comes in, if started with the -broadcast option, the ypbind process  broad-
       casts on the net trying to find an NIS server, either a ypserv process serving the domain or an rpc.nisd process in "YP-compatibility mode"
       serving	NIS+ directory with name the same as (case sensitive) the domain in the client request. Since the binding is established by broad-
       casting,  there must be at least one NIS server on the net. If started without the -broadcast option, ypbind process steps through the list
       of  NIS servers that was created by ypinit -c for the requested domain. There must be an NIS server process on at least one of the hosts in
       the NIS servers file. All the hosts in the NIS servers file must be listed in either the /etc/hosts or /etc/inet/ipnodes files  along  with
       their IP addresses. Once a domain is bound by ypbind, that same binding is given to every client process on the node. The ypbind process on
       the local node or a remote node may be queried for the binding of a particular domain by using the ypwhich(1) command.

       If ypbind is unable to speak to the NIS server process it is bound to, it marks the domain as unbound, tells the client	process  that  the
       domain is unbound, and tries to bind the domain once again. Requests received for an unbound domain will wait until the requested domain is
       bound. In general, a bound domain is marked as unbound when the node running the NIS server crashes or gets overloaded.	In  such  a  case,
       ypbind  will try to bind to another NIS server using the process described above.ypbind also accepts requests to set its binding for a par-
       ticular domain.	The request is usually generated by the ypset(1M) command. In order for ypset to work, ypbind must have been invoked  with
       flags -ypset or	-ypsetme.

OPTIONS

       -broadcast	       Send a broadcast datagram using UDP/IP  that requests the information needed to bind to a specific NIS server. This
			       option is analogous to ypbind with no options in earlier Sun releases and is recommended for ease of use.

       -ypset		       Allow users from any remote machine to change the binding by means of the ypset command. By  default,  no  one  can
			       change the binding. This option is insecure.

       -ypsetme 	       Only  allow  root  on  the  local  machine to change the binding to a desired server by means of the ypset command.
			       ypbind can verify the caller is indeed a root user by accepting such requests only on the  loopback  transport.	By
			       default, no external process can change the binding.

FILES

       /var/yp/binding/ypdomain/ypservers

       /etc/inet/hosts

       /etc/inet/ipnodes

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWnisu			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       svcs(1),  ypcat(1),  ypmatch(1),  ypwhich(1),  ifconfig(1M),  rpc.nisd(1M), svcadm(1M), ypinit(1M), ypset(1M), ypclnt(3NSL), hosts(4), ipn-
       odes(4), ypfiles(4), attributes(5), smf(5)

NOTES

       ypbind supports multiple domains. The  ypbind process can maintain bindings to several domains and their servers, the default domain is the
       one specified by the  domainname(1M) command at startup time.

       The  -broadcast option works only on the UDP transport. It is insecure since it trusts "any" machine on the net that responds to the broad-
       cast request and poses itself as an NIS server.

       The ypbind service is managed by the service management facility, smf(5), under the service identifier:

       svc:/network/nis/client:default

       Administrative actions on this service, such as enabling, disabling, or requesting restart, can be performed  using  svcadm(1M).  The  ser-
       vice's status can be queried using the svcs(1) command.

SunOS 5.10							    16 Aug 2004 							ypbind(1M)