ypbind
ypbind(8) ypbind(8)NAME
ypbind - NIS binding processSYNOPSIS
ypbind [ -c ] [ -d|-debug ] [ -broadcast ] [ -broken- server ] [ -ypset ] [ -ypsetme ] [ -no-ping ] [ -p port ][ -f configfile ] ypbind --versionDESCRIPTION
ypbind finds the server for NIS domains and maintains the NIS binding information. The client (normaly the NIS rou tines in the standard C library) could get the information over RPC from ypbind or read the binding files. The bind ing files resides in the directory /var/yp/binding and are conventionally named [domainname].[version]. The sup ported versions are 1 and 2. There could be serveral 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 doesn't get an response or the NIS server tells that he doesn't has this domain any longer, ypbind will search a new NIS server. All 15 min utes ypbind will check, 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 net work 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 server and binds to first one which answers. Unless the option -debug is used, ypbind detaches itself from the controlling terminal and puts itself into back ground. ypbind uses 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. 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 nisdo main. 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 broad cast. 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 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 han dle all the signals.OPTIONS
-broadcast Send a broadcast to request the information needed to bind to a specific NIS server. With this option, /etc/yp.conf will be ignored. -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. -ypsetme The same as -ypset, but only root on the local machine is allowed to chang the binding. Such requests are only allowd from loopback. -c ypbind only checks if the config file has syntax errors and exits. -debug starts ypbind in debug mode. ypbind will not put itself into background, and error messages and debug output are written to standard error. -broken-server lets ypbind accept answers from servers running on an illegal port number. This should usually be avoided, but is required by some ypserv(8) ver sions. -no-ping ypbind will not check if the binding is alive. This option is for use with dialup connections to pre vent ypbind from keeping the connection unnessecar ily open or causing autodials. -f configfile ypbind will use configfile and not /etc/yp.conf -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. --version Prints the version numberNOTES
Binding to multiple domains is tested and works. Load sharing between multiple servers for a single domain is not supported. 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.FILES
/etc/yp.conf configuration file. /var/yp/binding/[domainname].[version] binding file containing information about each NIS domain. /var/run/ypbind.pid contains the process id of the currently running ypbind master process.SEE ALSO
syslog(3), domainname(1), ypwhich(1), ypserv(8), ypset(8)AUTHOR
ypbind-mt was written by Thorsten Kukuk <kukuk@suse.de>. ypbind-mt Version 1.8 May 1999 ypbind(8)