ypserv.conf (5) Linux Manual Page

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

Description

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:

 host:domain:map:security

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.

Example:

 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:

host

IP address. Wildcards are allowed.

Examples:

 131.234. = 131.234.0.0/255.255.0.0
 131.234.214.0/255.255.254.0

domain

specifies the domain, for which this rule should be applied. An asterix as wildcard is allowed.

map

name of the map, or asterisk for all maps.

security

one of none, port, deny:

none

always allow access.

port

allow access if from port < 1024. Otherwise do not allow access.

deny

deny access to this map.

Files

/etc/ypserv.conf

See Also

ypserv(8), rpc.ypxfrd(8)

Warnings

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.

Author

Thorsten Kukuk <kukuk [at] thkukuk.de>