This chapter provides an overview of the LDAP naming service that is provided with the SolarisTM Operating System (Solaris OS). The naming services supported by the Solaris OS are described in detail in Part I, About Naming and Directory Services, in System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP).
This chapter covers the following topics:
A naming service stores information in a central place, which enables users, machines, and applications to communicate across the network. This information can include, for example, machine (host) names and addresses, user names, passwords, access permissions, group membership, and printers. Without a central naming service, each machine would have to maintain its own copy of this information. Naming service information can be stored in files, maps, or database tables. If you centralize all data, administration becomes easier.
The Solaris OS supports the following naming services:
DNS, the Domain Name System
/etc files, the original UNIX® naming system
NIS, the Network Information Service
NIS+, the Network Information Service Plus
LDAP, the Lightweight Directory Access Protocol
However, Sun's strategic direction is to move to LDAP-based naming services.
The LDAP naming service has the following advantages over other naming services:
Enables you to consolidate information by replacing application-specific databases, which reduces the number of distinct databases to be managed
Allows data to be shared by different naming services
Provides a central repository for data
Allows for more frequent data synchronization between master servers and replicas
Is multi-platform and multi-vendor compatible
The LDAP naming service has the following restrictions:
Clients prior to Solaris 8 are not supported.
Setting up and managing an LDAP naming service is more complex and requires careful planning.
An NIS client and a Native LDAP client cannot coexist on the same client machine.
The Solaris OS supports LDAP naming in conjunction with Sun Directory Server, as well as other LDAP directory servers. Although using Sun Directory Server is recommended, it is not required.
Moving from NIS to LDAP is a two-step process that involves data migration and client migration. The Solaris OS provides the NIS-to-LDAP transition service (N2L service), which accomplishes both steps.
The N2L service replaces existing NIS daemons on the NIS master server with NIS-to-LDAP transition daemons. The N2L service also creates an NIS-to-LDAP mapping file on that server. The mapping file specifies the mapping between NIS map entries and equivalent Directory Information Tree (DIT) entries in LDAP. An NIS master server that has gone through this transition is referred to as an N2L server.
The NIS slave servers continue to function in the usual manner. The slave servers periodically update their data from the N2L server as if the N2L server were a regular NIS master. A script, inityp2l, assists with the initial setup of these configuration files. When the N2L server has been established, you can maintain N2L by directly editing the configuration files.
The N2L service supports the following:
Import of NIS maps into the LDAP DIT
Client access to DIT information with the speed and extensibility of NIS
For details on how to migrate from NIS to LDAP, see Chapter 15, Transitioning From NIS to LDAP (Overview/Tasks), in System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP).
Although you can keep NIS+ data synchronized with LDAP, such synchronization has previously required an external agent. However, the NIS+ daemon now enables you to use an LDAP server as a data repository for NIS+ data. This feature enables NIS+ and LDAP clients to share the same naming service information. The transition from using NIS+ as the main naming service to using LDAP for the same role is therefore easier.
For details on how to migrate from NIS+ to LDAP, see Chapter 16, Transitioning From NIS+ to LDAP, in System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP).