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

The `nsswitch.conf` Template Files

Four nsswitch.conf(4) template files are provided with the Solaris operating environment to accommodate different naming services. Each of them provides a different default set of primary and subsequent information sources.

The four template files are the following.

LDAP template file. The nsswitch.ldap configuration file specifies the LDAP directory as the primary source of information for the machine.

Note –
In order to use LDAP naming services, you must also properly configure all LDAP client machines, in addition to modifying the nsswitch.conf. See Chapter 16, Client Setup (Task) for more information.
NIS+ template file. The nsswitch.nisplus configuration file specifies NIS+ as the primary source for all information except passwd, group, automount, and aliases. For those four files, the primary source is local /etc files and the secondary source is an NIS+ table. The [NOTFOUND=return] search criterion instructs the switch to stop searching the NIS+ tables if it receives a “No such entry” message from them. It searches through local files only if the NIS+ server is unavailable
NIS template file. The nsswitch.nis configuration file is almost identical to the NIS+ configuration file, except that it specifies NIS maps in place of NIS+ tables. Because the search order for passwd and group is files nis, you don't need to place the + entry in the /etc/passwd and /etc/group files
Files template file. The nsswitch.files configuration file specifies local /etc files as the only source of information for the machine. There is no “files” source for netgroup, so the client will not use that entry in the switch file

Copy the template file that most closely meets your requirements to thensswitch.conf configuration file and then modify the file as needed.

For example, to use the LDAP template file, you would type the following command.

mymachine# cp nsswitch.ldap nsswitch.conf

The Default Switch Template Files

The following are the four switch files supplied with Solaris operating environment.

Example 2–1 NIS+ Switch File Template (`nsswitch.nisplus`)

#
#
# /etc/nsswitch.nisplus:
#
#
# An example file that could be copied over to /etc/nsswitch.conf;
# it uses NIS+ (NIS Version 3) in conjunction with files.
#
# "hosts:" and "services:" in this file are used only if the
# /etc/netconfig file has a "-" for nametoaddr_libs of "inet"
# transports.
 
# the following two lines obviate the "+" entry in /etc/passwd 
# and /etc/group.
passwd: files nisplus
group: files nisplus
# consult /etc "files" only if nisplus is down. 
hosts: nisplus [NOTFOUND=return] files
# Uncomment the following line, and comment out the above, to use 
# both DNS and NIS+. You must also set up the /etc/resolv.conf 
# file for DNS name server lookup. See resolv.conf(4).
# hosts: nisplus dns [NOTFOUND=return] files
services: nisplus [NOTFOUND=return] files
networks: nisplus [NOTFOUND=return] files
protocols: nisplus [NOTFOUND=return] files
rpc: nisplus [NOTFOUND=return] files
ethers: nisplus [NOTFOUND=return] files
netmasks: nisplus [NOTFOUND=return] files	
bootparams: nisplus [NOTFOUND=return] files
publickey: nisplus
netgroup: nisplus
automount: files nisplus
aliases: files nisplus
sendmailvars: files nisplus

Example 2–2 NIS Switch File Template

#
# /etc/nsswitch.nis:
#
# An example file that could be copied over to /etc/nsswitch.conf;
# it uses NIS (YP) in conjunction with files.
#
# "hosts:" and "services:" in this file are used only if the
# /etc/netconfig file has a "-" for nametoaddr_libs of "inet"
# transports.
#
# the following two lines obviate the "+" entry in /etc/passwd
# and /etc/group.
passwd: files nis
group: files 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: nis [NOTFOUND=return] files
netmasks: nis [NOTFOUND=return] files	
bootparams: nis [NOTFOUND=return] files
publickey: nis [NOTFOUND=return] files
netgroup: nis
automount: files nis
aliases: files nis
# for efficient getservbyname() avoid nis
services: files nis
sendmailvars: files

Example 2–3 Files Switch File Template

#
# /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 has a "-" for nametoaddr_libs of "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 will notuse
# netgroups at all.
netgroup: files
automount: files
aliases: files
services: files
sendmailvars: files

Example 2–4 LDAP Switch File Template

 #
# /etc/nsswitch.ldap:
#
# An example file that could be copied over to /etc/nsswitch.conf; it
# uses LDAP in conjunction with files.
#
# "hosts:" and "services:" in this file are used only if the
# /etc/netconfig file has a "-" for nametoaddr_libs of "inet" transports.

# the following two lines obviate the "+" entry in /etc/passwd 
and /etc/group.
passwd:     files ldap
group:      files ldap

hosts:      ldap [NOTFOUND=return] files

networks:   ldap [NOTFOUND=return] files
protocols:  ldap [NOTFOUND=return] files
rpc:        ldap [NOTFOUND=return] files
ethers:     ldap [NOTFOUND=return] files
netmasks:   ldap [NOTFOUND=return] files
bootparams: ldap [NOTFOUND=return] files
publickey:  ldap [NOTFOUND=return] files

netgroup:   ldap

automount:  files ldap
aliases:    files ldap

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

The `nsswitch.conf` File

The default nsswitch.conf file that is installed when you install the Solaris operating environment for the first time is determined by which naming service you select during the Solaris software installation process. Each line of that file identifies a particular type of network information, such as host, password, and group, followed by one or more sources, such as NIS+ tables, NIS maps, the DNS hosts table, or local /etc, where the client is to look for that information. When you chose a naming service, the switch template file for that service is copied to create the new nsswitch.conf file. For example, if you choose NIS+, the nsswitch.nisplus file is copied to create a new nsswitch.conf file.

An /etc/nsswitch.conf file is automatically loaded into every machine's /etc directory by the Solaris 9 release software, along with the following alternate (template) versions.

/etc/nsswitch.nisplus
/etc/nsswitch.nis
/etc/nsswitch.files
/etc/nsswitch.ldap

These alternate template files contain the default switch configurations used by the NIS+ and NIS services, local files, and LDAP. No default file is provided for DNS, but you can edit any of these files to use DNS. See Chapter 5, DNS Administration (Reference). When the Solaris operating environment is first installed on a machine, the installer selects the machine's default naming service: NIS+, NIS, local files, or LDAP. During installation, the corresponding template file is copied to /etc/nsswitch.conf. For example, for a machine client using NIS+, the installation process copies nsswitch.nisplus to nsswitch.conf.

If your network is connected to the Internet and you want users to be able to access Internet hosts using DNS, you must enable DNS forwarding.

Unless you have an unusual namespace, the default template file as copied to nsswitch.confshould be sufficient for normal operation.

The nsswitch.conf Template Files