NIS Maps
NIS stores information in a set of files called maps.
NIS maps were designed to replace traditional UNIX /etc files, as well as other configuration files, so they store much more than names and addresses. As a result, the NIS namespace has a large set of maps, as shown in the NIS Maps table below.
NIS maps are essentially two-column tables. One column is the key and the other column is information about the key. NIS finds information for a client by searching through the keys. Thus, some information is stored in several maps because each map uses a different key. For example, the names and addresses of workstations are stored in two maps: hosts.byname and hosts.byaddr. When a server has a workstation's name and needs to find its address, it looks in the hosts.byname map. When it has the address and needs to find the name, it looks in the hosts.byaddr map.
| NIS Map | Description |
|---|---|
| bootparams | Lists the names of the diskless clients and the location of the files they need during booting. |
| ethers.byaddr | Lists the Ethernet addresses of workstations and their corresponding names. |
| ethers.byname | Lists the names of workstations and their corresponding Ethernet addresses. |
| group.bygid | Provides membership information about groups, using the group ID as the key. |
| group.byname | Provides membership information about groups, using the group name as the key. |
| hosts.byaddr | Lists the names and addresses of workstations, using the address as the key. |
| hosts.byname | Lists the names and addresses of workstations, using the name as the key. |
| mail.aliases | Lists the mail aliases in the namespace and all the workstations that belong to them. |
| mail.byaddr | Lists the mail aliases in the namespace, using the address as the key. |
| netgroup | Contains netgroup information, using the group name as the key. |
| netgroup.byhost | Contains information about the netgroups in the namespace, using workstation names as the key. |
| netgroup.byuser | Contains netgroup information, using the user as the key. |
| netid.byname | Contains the Secure remote procedure call (RPC) netname of workstations and users, along with their user IDs and group IDs. |
| netmasks.byaddr | Contains network masks used with Internet Protocol (IP) subnetting, using the address as the key. |
| networks.byaddr | Contains the names and addresses of the networks in the namespace, and their Internet addresses. |
| networks.byname | Contains the names and addresses of the networks in the namespace, using the names as the key. |
| passwd.byname | Contains password information, with the username as the key. |
| passwd.byuid | Contains password information, with the user ID as the key. |
| protocols.byname | Lists the network protocols used. |
| protocols.bynumber | Lists the network protocols used but uses their number as the key. |
| publickey.byname | Contains public and secret keys for Secure RPC. |
| rpc.bynumber | Lists the known program name and number of RPCs. |
| services.byname | Lists the available Internet services. |
| ypservers | Lists the NIS servers in the namespace, along with their IP addresses. |
Network Information Service contains detail about the development and use of NIS.