nsswitch.conf File -- Specifying Which Name Service to Use

The /etc/nsswitch.conf file defines the search order of the network databases. The Solaris installation program creates a default /etc/nsswitch.conf file for the local machine, based on the name service you indicate during the installation process. If you selected the "None" option, indicating local files for name service, the resulting nsswitch.conf file resembles Example 4-5.

Example 4-5 nsswitch.conf for Networks Using Files for Name Service

# /etc/nsswitch.files:
#
# An example file that could be copied over to /etc/nsswitch.conf;
# it does not use any naming service.
#
# "hosts:" and "services:" in this file are used only if the
# /etc/netconfig file contains "switch.so" as a
# nametoaddr library for "inet" transports.

passwd:          files
group:           files
hosts:           files
networks:        files
protocols:       files
rpc:             files
ethers:          files
netmasks:        files	
bootparams:      files
publickey:       files
# At present there isn't a 'files' backend for netgroup; the
# system will figure it out pretty quickly,
# and won't use netgroups at all.
netgroup:        files
automount:       files
aliases:         files
services:        files
sendmailvars:    files

The nsswitch.conf(4) man page describes the file in detail. Its basic syntax is:

database name-service-to-search

The database field can list one of many types of databases searched by the operating system. For example, it could indicate a database affecting users, such as passwd or aliases, or a network database. The parameter name-service-to-search can have the values files, nis, or nis+ for the network databases. (The hosts database can also have dns as a name service to search.) You can also list more than one name service, such as nis+ and files.

In Example 4-5, the only search option indicated is files. Therefore, the local machine gets security and automounting information, in addition to network database information, from files located in its /etc and /etc/inet directories.

Changing nsswitch.conf

The /etc directory contains the nsswitch.conf file created by the Solaris installation program. It also contains template files for the following name services:

• nsswitch.files

• nsswitch.nis

• nsswitch.nis+

If you want to change from one name service to another, you can copy the appropriate template to nsswitch.conf. You can also selectively edit the nsswitch.conf file, and change the default name service to search for individual databases.

For example, on a network running NIS, you might have to change the nsswitch.conf file on diskless clients. The search path for the bootparams and ethers databases must list files as the first option, and nis. Example 4-6 shows the correct search paths.

Example 4-6 nsswitch.conf for a Diskless Client on a Network Running NIS

## /etc/nsswitch.conf:#
.
.
passwd:        files nis
group:         file nis

# consult /etc "files" only if nis is down.
hosts:         nis    [NOTFOUND=return] files
networks:      nis    [NOTFOUND=return] files
protocols:     nis    [NOTFOUND=return] files
rpc:           nis    [NOTFOUND=return] files
ethers:        files  [NOTFOUND=return] nis
netmasks:      nis    [NOTFOUND=return] files	
bootparams:    files  [NOTFOUND=return] nis
publickey:     nis    netgroup:         nis

automount:     files nis
aliases:       files nis

# for efficient getservbyname() avoid nis
services:      files nis
sendmailvars:  files

For complete details on the name service switch, refer to Solaris Naming Administration Guide.