ypbind (8)

SYNOPSIS

/sbin/ypbind [ -v | --version ] [ -h | --help ] [ -d | --debug ] [ --ipc ] [ --mmap ] [ --broken_server ] [ --ypset ] [ --ypsetme ] [ --broadcast ] [ --no-ping\ |\ --ping\ N ]

DESCRIPTION

ypbind finds the server for a NIS domain and stores the information about it in a binding file. The binding file resides in the directory /var/yp/binding and is conventionally named domainname.version . The only supported version is version 2.

Unless the option -debug is used, ypbind detaches itself from the controlling terminal and puts itself into background. ypbind uses syslog() 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 are

domain nisdomain server hostname

Use server hostname for the domain nisdomain .

domain nisdomain broadcast

Use broadcast on the local net for domain nisdomain .

ypserver hostname

Use server server for the local domain. The IP-address of server must be listed in /etc/hosts .

If the file does not exist of if there are no valid entries, ypbind broadcasts on the local net looking for a NIS server for the local domain.

ypbind is split into two processes. The master process services RPC requests asking for binding info. The slave process initializes the binding and checks it periodically. Upon failure, the binding is invalidated and the process tries again to find a valid server.

OPTIONS

ypset (8) may be used to change the binding for a domain.

ypset (8) may only be used from the local host to change the binding for a domain.

starts ypbind in debug mode. ypbind will not put itself into background, and error messages and debug output are written to standard error.

lets ypbind use IPC for the master-slave communication. It requires a kernel with IPC enabled. You must use this, if your root-Filesystem is on NFS.

lets ypbind use mmap for the master-slave communication. This may fail with some older kernels.

lets ypbind accept answers from servers running on an illegal port number. This should usually be avoided, but is required on Solaris 2.4 (there should be a patch for Solaris which fixes this broken behaviour.)

prevents ypbind from continually checking if the binding is alive. This option is intented for use with dialup connections to prevent ypbind from keeping the connection unnessecarily open or causing autodials.

make ypbind check every N seconds to see if the binding is alive. If the binding appears to have died, ypbind will attempt to find a new NIS server.

If do not have a broadcast listed for you local NIS domain, ypbind will stop working if the server it is bound to goes away. This option instructs ypbind to fallback to broadcasting if it runs out of servers for binding for the local NIS domain. This option is the equivalent of adding a line like this in /etc/yp.conf : domain NISDOMAINNAME broadcast .

FILES

/etc/yp.conf - configuration file.

/var/yp/binding/ domainname.version - binding file containing information about domain .

/var/run/ypbind.pid - contains the process id of the currently running ypbind master process. ypbind sets a write lock to this file to prevent multiple copies of itself from running.

BUGS

Binding to multiple domains is untested. ypbind will only bind to one single server per domain. Load sharing between multiple servers for a single domain is not supported.

AUTHOR

ypbind was written by Swen Thuemmler <swen@uni-paderborn.de>. Michael Rausch <mrausch@ernie.mi.uni-koeln.de> added support for SysV-IPC. Numerous bugfixes from other contributors.