ypserv.conf (5) - Linux Man Pages

ypserv.conf: configuration file for ypserv and rpc.ypxfrd


ypserv.conf - configuration file for ypserv and rpc.ypxfrd


ypserv.conf is an ASCII file which contains some options for ypserv. It also contains a list of rules for special host and map access for ypserv and rpc.ypxfrd. This file will be read by ypserv and rpc.ypxfrd at startup, or when receiving a SIGHUP signal.

There is one entry per line. If the line is a option line, the format is:

   option: argument

The line for an access rule has the format:


All rules are tried one by one. If no match is found, access to a map is allowed.

Following options exist:

files: 30
This option specifies, how many database files should be cached by ypserv. If 0 is specified, caching is disabled. Decreasing this number is only possible, if ypserv is restarted.
trusted_master: server
If this option is set on a slave server, new maps from the host server will be accepted as master. The default is, that no trusted master is set and new maps will not be accepted.


   trusted_master: ypmaster.example.org
slp: [yes|<no>|domain]
If this option is enabled and SLP support compiled in, the NIS server registers itself on a SLP server. If the variable is set to domain, an attribute domain with a comma seperated list of supported domainnames is set. Else this attribute will not be set. The default is "no" (disabled).
xfr_check_port: [<yes>|no]
With this option enabled, the NIS master server have to run on a port < 1024. The default is "yes" (enabled).

The field descriptions for the access rule lines are:

IP address. Wildcards are allowed.


   131.234. =
specifies the domain, for which this rule should be applied. An asterix as wildcard is allowed.
name of the map, or asterisk for all maps.
one of none, port, deny:
always allow access.
allow access if from port < 1024. Otherwise do not allow access.
deny access to this map.




The access rules for special maps are no real improvement in security, but they make the life a little bit harder for a potential hacker.

Solaris clients don't use privileged ports. All security options which depend on privileged ports cause big problems on Solaris clients.


Thorsten Kukuk <kukuk [at] thkukuk.de>


ypserv(8), rpc.ypxfrd(8)