ypbind - Unix, Linux Command
ypbind - NIS binding process
-c ] [
-d|-debug ] [
-v|-verbose ] [
-broadcast ] [
-broken-server ] [
-ypset ] [
-ypsetme ] [
-no-ping ] [
-p port ] [
-f configfile ] [
-local-only ] [
-ping-interval ping-interval ]
ypbind finds the server for NIS domains and maintains the NIS binding
information. The client (normaly 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 then one domain.
After a binding has been established,
ypbind will send YPPROC_DOMAIN requests to the current NIS server at 20 seconds
intervals. If it doesnt get an response or the NIS server reports that he
doesnt 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.
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. Valid entries
domain nisdomain server hostname Use server
hostname for the domain
nisdomain. You could have more then one entry of this type for a single domain.
domain nisdomain broadcast Use broadcast on the local net for domain
ypserver hostname Use server
server for the local domain.
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,
not switch to use broadcast.
ypbind will try at first
/etc/hosts and then
DNS for resolving the hosts names from
ypbind couldnt reconfigure the search order, it will use only
DNS isnt available, you could only use IP-addresses in
/etc/hosts. ypbind could only reconfigure the search order with glibc 2.x.
-broadcast option is specified,
ypbind will ignore the configuration file.
If the file does not exist or if there are no valid entries,
ypbind is a special version which uses
pthreads. It will start 2 more threads. The master process services RPC requests
asking for binding info. The first thread initializes the binding and
checks it periodically. Upon failure, the binding is invalidated and
the process tries again to find a valid server. The second thread
will handle all the signals.
Send a broadcast to request the information needed to bind to a
specific NIS server. With this option,
/etc/yp.conf will be ignored.
root from any remote machine to change the binding for a domain via the
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 chang the binding. Such requests
are only allowd from
ypbind only checks if the config file has syntax errors and exits.
ypbind in debug mode.
ypbind will not put itself into background, and error messages and debug
output are written to standard error.
ypbind to syslog(2) any and all changes in the server its bound to.
ypbind accept answers from servers running on an illegal port number. This should
usually be avoided, but is required by some
ypbind will not check if the binding is alive. This option is for use with
dialup connections to prevent
ypbind from keeping the connection unnessecarily open or causing autodials.
-p port |
ypbind will bind itself to this port.
This makes it possible to have a router filter packets
to the NIS ports, so that access to this service from
hosts on the Internet can be restricted.
-f configfile |
ypbind will use
configfile and not
ypbind will only bind to the loopback device and is not reacheable from
a remote network.
-ping-interval ping-interval |
The default value for
ypbind to check, if a NIS server is still reacheable, is 20 seconds.
With this options another frequency in seconds can be specified.
Prints the version number
Binding to multiple domains is tested and works.
Load sharing between multiple servers for a single domain is
ypbind will always try to bind a domain to a server. If there is no valid
server in the list or answers to a broadcast, the domain is unbounded.
binding file containing information about each NIS domain.
contains the process id of the currently running
ypbind master process.
ypbind-mt was written by Thorsten Kukuk <email@example.com>.