--- name: "ypbind" section: "8" platform: "linux" package: "ypbind-mt" version: "2.7.2-3+b2" release: "Debian 13 (Trixie)" platforms: ["linux", "freebsd", "openbsd"] url: "https://new.carta.tech/ypbind" --- # ypbind(8) NIS binding process ## NAME ypbind - NIS binding process ## SYNOPSIS **ypbind** \[-c\] \[-d \| -debug\] \[-verbose\] \[-n \| -forground\] \[-broadcast\] \[-broken-server\] \[-ypset\] \[-ypsetme\] \[-no-ping\] \[-f *configfile*\] \[-local-only\] \[-ping-interval *ping-interval*\] \[-p *port*\] **ypbind** --version ## DESCRIPTION **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, 2 and 3. There could be several such files since it is possible for an NIS client to be bound to more than one domain. After a binding has been established, **ypbind** will send YPPROC\_DOMAIN requests to the current NIS server at 5 minutes 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. 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 in the order in which they are listed in the config file and use the 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)](/syslog/3.md) 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. ## 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)](/ypset/8.md) 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 change the binding. Such requests are only allowed from **loopback**. - **-c** **ypbind** only checks if the config file has syntax errors and exits. - **-d**, **-debug** starts **ypbind** in debug mode. **ypbind** will not put itself into background, and error messages and debug output are written to standard error. - **-n**, **-foreground** **ypbind** will not put itself into backgroun. - **-v**, **-verbose** Causes **ypbind** to [syslog(2)](/syslog/2.md) any and all changes in the server its bound to. - **-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)](/ypserv/8.md) versions. - **-no-ping** **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 auto-dials. - **-f** configfile **ypbind** will use **configfile** and not /etc/yp.conf - **-local-only** **ypbind** will only bind to the loopback device and is not reachable from a remote network. - **-i**, **-ping-interval** ping-interval 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. - **-p** port The privileged port number that **ypbind** should use to bind itself. - **--version** Prints the version number ## 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)](/syslog/3.md), [**domainname**(1)](/domainname/1.md), [**yp.conf**(5)](/yp.conf/5.md), [**ypdomainname**(8)](/ypdomainname/8.md), [**ypwhich**(1)](/ypwhich/1.md), [**ypserv**(8)](/ypserv/8.md), [**ypset**(8)](/ypset/8.md) ## AUTHOR **ypbind-mt** was written by Thorsten Kukuk \.