Using an NIS slave on your storage system can improve the performance of your storage system. 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.
The NIS slave improves performance by establishing a contact with an NIS master server and performing the following two tasks:
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.
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.