YP(8) | System Manager's Manual | YP(8)

# NAME

`yp` — description of the YP subsystem

# SYNOPSIS

`ypinit` | `-m` [domainname]

`ypinit` | `-s` master_server [domainname]

`ypinit` | `-u` [domainname]

`ypbind` | [`-insecure`] [`-ypset`] [`-ypsetme`]

`ypset` | [`-d` domain] [`-h` host] server

`yppoll` | [`-d` domain] [`-h` host] mapname

`ypcat` | [`-kt`] [`-d` domainname] mapname

`ypcat` | `-x`

`ypmatch` | [`-kt`] [`-d` domainname] key ... mapname

`ypmatch` | `-x`

`ypwhich` | [`-t`] [`-d` domain] [[`-h`] host]

`ypwhich` | [`-t`] [`-d` domain] [`-h` host] `-m` [mname]

`ypwhich` | `-x`

`ypserv` | [`-1dx`] [`-a` aclfile]

`ypxfr` | [`-cf`] [`-C` tid prog ipadd port] [`-d` domain] [`-h` host] [`-s` domain] mapname

`yppush` | [`-v`] [`-d` domainname] [`-h` hostname] mapname

# DESCRIPTION

The `YP` subsystem allows network management of passwd, group, and hosts file entries through the functions getpwent(3), getgrent(3) and gethostbyname(3). A number of other databases can be network-managed as well, and have their respective functions. `YP` also provides hooks for numerous other client programs such as amd(8) and rpc.bootparamd(8) to access distributed and shareable versions of their maps through `YP`. The YP subsystem requires that portmap(8) be running, since the entire subsystem uses the RPC subsystem.

`ypinit` is used to initialize `YP` as a master or a slave. This creates various files in /var/yp. After running `ypinit` `-m`, optionally edit /var/yp/DOMAINNAME/Makefile to change settings, for example to switch from the default backwards compatible mode to secure mode. Finally, always run make(1) in /var/yp. See Makefile.yp(8) for details.

If set up as a slave, the required databases are automatically copied from the specified server.

The `YP` client subsystem is started automatically in /etc/rc if the directory /var/yp/binding exists. The client subsystem can be turned on and off by creating or deleting that directory. ypbind(8) will create that directory if run by hand.

The `YP` server subsystem is started automatically in /etc/rc if the directory /var/yp/DOMAINNAME exists. This directory is automatically created by ypinit(8) (which initializes the machine as a `YP` server).

If `ypbind` cannot find a server, the system behaves the same way as Sun's code does: it hangs.

# FILES

/var/yp/Makefile.main
  Top level YP Makefile
/var/yp/Makefile.yp
  YP maps Makefile

# SEE ALSO

domainname(1), ypcat(1), ypmatch(1), ypwhich(1), yp_bind(3), defaultdomain(5), group(5), passwd(5), resolv.conf(5), Makefile.yp(8), portmap(8), ypbind(8), ypinit(8), yppoll(8), yppush(8), ypserv(8), ypset(8), ypxfr(8)

# HISTORY

This free `YP` subsystem is thought to be compatible with Sun's implementation. It is, of course, not compatible with `NIS+` or any other “secure” `YP` subsystem other than the native one.

The name `YP` stands for Yellow Pee.

The ypbind, most library components, and userland programs were implemented by Theo de Raadt <deraadt@theos.com>. The current getpwent(3) implementation was done by Jason Downs <downsj@downsj.com>. The server component was implemented by Mats O Jansson <moj@stacken.kth.se>.

September 27, 2022 | Debian