ypbind - NIS binding process
ypbind [ -c ] [ -d|-debug ] [ -broadcast ] [ -broken-server ] [ -ypset
] [ -ypsetme ] [ -no-ping ] [ -f configfile ] [ -local-only ] [ -ping-
interval ping-interval ] [ -no-dbus ]
ypbind finds the server for NIS domains and maintains the NIS binding
information. The client (normally the NIS routines in the standard C
library) could get the information over RPC from ypbind or read the
binding files. The binding files resides in the directory
/var/yp/binding and are conventionally named [domainname].[version].
The supported versions are 1 and 2. There could be several such files
since it is possible for an NIS client to be bound to more than one
After a binding has been established, ypbind will send YPPROC_DOMAIN
requests to the current NIS server at 20 seconds intervals. If it
doesn’t get an response or the NIS server reports that he doesn’t have
this domain any longer, ypbind will search for a new NIS server. All 15
minutes ypbind will check to see if the current NIS server is the
fastest. If it find a server which answers faster, it will switch to
this server. You could tell ypbind to use network broadcasts to find a
new server, what is insecure, or you could give it a list of known
secure servers. In this case ypbind will send a ping to all servers
and binds to first one which answers.
Unless the option -debug is used, ypbind detaches itself from the
controlling terminal and puts itself into background. ypbind uses
syslog(3) for logging errors and warnings. At startup or when
receiving signal SIGHUP, ypbind parses the file /etc/yp.conf and tries
to use the entries for its initial binding.
A broadcast entry in the configuration file will overwrite a
ypserver/server entry and a ypserver/server entry broadcast. If all
given server are down, ypbind will not switch to use broadcast. ypbind
will try at first /etc/hosts and then DNS for resolving the hosts names
from /etc/yp.conf. If ypbind couldn’t reconfigure the search order, it
will use only DNS. If DNS isn’t available, you could only use IP-
addresses in /etc/hosts. ypbind could only reconfigure the search
order with glibc 2.x. If the -broadcast option is specified, ypbind
will ignore the configuration file. If the file does not exist or if
there are no valid entries, ypbind exit.
This ypbind version listens for DBUS messages from NetworkManager. If
no NetworkManager is running at startup, ypbind will behave as usual
and assumes there is a working network connection. If NetworkManager is
running on the system, ypbind will only search and provide NIS
informations, if NetworkManager tells that a network connection is
available. If NetworkManager establishes a connection, ypbind will
reread all configuration files, registers at the local portmapper and
try to search NIS servers. If NetworkManager drops a connection, ypbind
will unregister from portmapper.
Send a broadcast to request the information needed to bind to a
specific NIS server. With this option, /etc/yp.conf will be
-ypset Allow root from any remote machine to change the binding for a
domain via the ypset(8) command. By default, no one can change
the binding. This option is really insecure. If you change a
binding for a domain, all the current known servers for this
domain will be forgotten. If the new server goes down, ypbind
will use the old searchlist.
The same as -ypset, but only root on the local machine is
allowed to change the binding. Such requests are only allowed
-c ypbind only checks if the config file has syntax errors and
-debug starts ypbind in debug mode. ypbind will not put itself into
background, and error messages and debug output are written to
lets ypbind accept answers from servers running on an illegal
port number. This should usually be avoided, but is required by
some ypserv(8) versions.
ypbind will not check if the binding is alive. This option is
for use with dialup connections to prevent ypbind from keeping
the connection unnecessarily open or causing autodials.
ypbind will use configfile and not /etc/yp.conf
ypbind will only bind to the loopback device and is not
reachable from a remote network.
The default value for ypbind to check, if a NIS server is still
reachable, is 20 seconds. With this options another frequency
in seconds can be specified.
Disables DBUS support if compiled int.
Prints the version number
binding file containing information about each NIS domain.
contains the process id of the currently running ypbind master
syslog(3), domainname(1), yp.conf(5), ypdomainname(8), ypwhich(1),
ypbind-mt was written by Thorsten Kukuk <firstname.lastname@example.org>.