Chapter 1 Overview of the Migration Process for Directory Server

This chapter describes the steps involved in migrating to Directory Server 6.2. Directory Server 6.2 provides a migration tool, dsmig, that automates aspects of the migration for certain platform/version combinations. If servers within your topology fall outside of these combinations, the same migration steps must be performed manually.

This chapter includes the following topics:

Before You Migrate

This chapter provides an overview of the upgrade and data migration process.

Before upgrading, familiarize yourself with the new features and fixes available in the current version. Take the opportunity to review design decisions made during implementation of existing directory services. For a description of all new features and fixes, see What’s New at a Glance in Sun Java System Directory Server Enterprise Edition 6.2 Evaluation Guide. For information about the new features that specifically affect migration, see Chapter 5, Architectural Changes in Directory Server.

Prerequisites to Migrating a Single Directory Server Instance From 5.1 and Later

Before migrating from a 5.1 or later server instance, ensure that the following prerequisites are met:

Directory Server 6.2 must be installed. The new server can be installed on the same machine as the existing server or on a different machine.
Ensure that the new machine has sufficient local disk space to house binaries and databases for both the old and new servers, and also enough extra space to hold LDIF files containing the entries in all existing suffixes. You can estimate the local disk space required as somewhat larger than the following calculation.
```
local space required = 2 * (space for existing server) + (space for LDIF files)
```
If you are using the automatic migration tool, the following two prerequisites must be met:
- The existing server instance must be stopped cleanly.
- If the new server is located on a different machine, a complete image of the original server instance must be created on the new machine. This includes all schema files, configuration files, security files, and database files, in an identical layout to the original server root.
To determine whether you should use automatic or manual migration, see Deciding on Automatic or Manual Migration.
If your Directory Server deployment includes Identity Synchronization for Windows, you must uninstall Identity Synchronization for Windows before migrating to Directory Server 6.2. For information about migrating Identity Synchronization for Windows, see Chapter 7, Migrating Identity Synchronization for Windows.

Deciding on the New Product Distribution

Directory Server 6.2 is provided in two distributions:

Java Enterprise System distribution. This distribution takes the form of operating system-specific packages, such as pkg for Solaris and rpm for Linux.
Compressed archive (zip) distribution.

There are two major differences between these two distributions:

Installation from zip can be done anywhere on the system and as a non-root user. The Java Enterprise System distribution requires installation as a super user. It is also more difficult from an automated deployment perspective to install the packages anywhere but in the default location.
The zip distribution can be installed as many times as required and multiple distinct versions of the same product can coexist on a single operating system instance. This is not true for the Java Enterprise System distribution. The new version of certain shared component packages required by Directory Server are incompatible with the previous version of these packages. When you migrate to the new version of Directory Server using the Java Enterprise System distribution, the old Directory Server version will no longer run on that machine.

Depending on your environment and the specific requirements of your organization, select the appropriate packaging format.

Outline of Migration Steps

Migration to Directory Server 6.2 can be broken down into the following distinct steps:

Migrating the Schema
Migrating the Security Settings
Migrating the Configuration
Migrating the Data
Migrating the Plug-Ins
Post-migration tasks

To avoid unforeseen problems with the migration, these steps should be performed in the order listed above. In certain cases, you can automate some or all of these steps, using the dsmig command. The following section indicates what can be automated and what must be done manually, depending on your existing deployment.

Deciding on Automatic or Manual Migration

This section provides a table that shows when you can use dsmig and when you need to migrate manually. It is based on the migration steps described in the previous section.

Table 1–1 Migration Matrix Showing Support for Automated Migration


Migrating To		Migration Step
Software (32/64–bit)	OS	Schema	Config	Security	Data	Plug-Ins
Any	Any	Manual	Manual	Manual	Manual	Manual
Different	Any	`dsmig`	`dsmig`	`dsmig`	Manual	Manual
Same	Different	`dsmig`	`dsmig`	`dsmig`	Manual	Manual
Same	Same	`dsmig`	`dsmig`	`dsmig`	Manual for 5.1 `dsmig` for 5.2	Manual

The following two chapters explain how to perform each migration step outlined above, either automatically, or manually. For information on automatic migration, see Chapter 2, Automated Migration Using the dsmig Command. For information on manual migration, see Chapter 3, Migrating Directory Server Manually.