System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP)

The /var/yp/securenets File

As with the previous NSKit release, the /var/yp/securenets file is now used to limit access to NIS services. If such a file exists on an NIS server, the server only answers queries or supplies maps to machines and networks whose IP addresses are listed in the file. For the file format, see securenets(4).

The following is an example of a securenets file.


255.255.255.10	 192.168.0.1
host    13.13.14.1
host    13.13.14.2

where 255.255.255.10 is the netmask and 13.13.13.255 is the network address. For the set up in line 1, ypserv responds to only those addresses in the subnet 13.13.13.255 range.

If you modify entries in the /var/yp/securenets file, you must kill and restart the ypserv and ypxfrd daemons.