How using NIS slaves can improve performance

Host-name resolution by using a hosts map can have a performance impact because each query for the hosts map is sent across the network to the NIS server. You can improve the performance of your storage system by downloading the maps and listening for updates from the NIS master server.

The NIS slave improves performance by establishing contact with an NIS master server and performing the following two tasks:

•	Downloading the maps from the NIS master server

You can download the maps from the NIS master server to the NIS slave by running the yppush command from the NIS server. You can also download the maps by disabling and then enabling the NIS slave from your storage system. After the maps are downloaded, they are stored in the /etc/yp/nis_domain_name directory. The NIS slave then services all the NIS requests from your storage system by using these maps. The NIS slave checks the NIS master every 45 minutes for any changes to the maps. If there are changes, they are downloaded.

•	Listening for updates from the NIS master

When the maps on the NIS master are changed, the NIS master administrator can optionally notify all slaves. Therefore, in addition to periodically checking for updates from the NIS master, the NIS slave also listens for updates from the master.

You cannot configure the NIS slave during the setup procedure. To configure the NIS slave after the setup procedure is complete, you need to enable NIS slave by setting options nis.slave.enable to on.

Note: The NIS slave does not respond to remote NIS client requests and therefore cannot be used by other NIS clients for name lookups.