Checklist: Performing an Interforest Migration

Applies To: Windows Server 2008, Windows Server 2008 R2, Windows Server 2012, Windows Server 2012 R2

Applies to: Active Directory Migration Tool 3.2 (ADMT 3.2)

Migrating Active Directory domains between forests (interforest migration) involves relocating objects from source domains in one forest to target domains in another forest. You might have to restructure Active Directory domains between forests for the following reasons:

  • To migrate a pilot domain into your production environment

  • To merge your Active Directory forest with the forest of another organization and consolidate the two information technology (IT) infrastructures

Task Reference

Review the Active Directory Migration Tool (ADMT) preinstallation instructions.

Installing ADMT in the Target Domain

To migrate computers running Windows Server 2003, Windows Vista (without Service Pack 1), Windows XP, and Microsoft Windows 2000 (using ADMT 3.1) to a target domain, first set the following registry key on the target domain controllers:

Note
This registry key does not need to be set to migrate computers that run later versions of Windows (such as Windows Server 2008, Windows Server 2008 R2, Windows 7, or Windows Vista SP1) or that installed the RODC client compatibility pack (hotfix 944043).

Registry path: HKLM\System\CurrentControlSet\Services\Netlogon\Parameters

Registry value: AllowNT4Crypto

Type: REG_DWORD

Data: 1

Note

This registry setting corresponds to the Allow cryptography algorithms compatible with Windows NT 4.0 setting in Group Policy.

For more information about making this change using Group Policy, see Microsoft Knowledge Base article 942564 (https://support.microsoft.com/default.aspx?scid=kb;EN-US;942564).

For more information about the RODC client compatibility pack, see Microsoft Knowledge Base article 944043 (https://support.microsoft.com/kb/944043).

For any migration tasks that use agent deployment and where Windows Firewall is in use, enable the File and Printer Sharing exception. This can include migration for the following situations:

  • Migrating workstation computers and member servers that are running Windows Server 2003 or Windows XP or later.

  • Migrating security settings or performing security translation

For more information about making this change in Windows Firewall, see Enable or Disable the File and Printer Sharing Exception (https://go.microsoft.com/fwlink/?LinkID=119315).

Prepare to restructure Active Directory domains within a forest. This task has the following subtasks:

  • Determine your account migration process.

  • Assign object roles and locations.

  • Develop a test plan for your migration.

  • Create a rollback plan.

  • Manage users, groups, and user profiles.

  • Create a user communication plan.

Installing ADMT in the Target Domain

Planning to Restructure Active Directory Domains Between Forests

Prepare the source and target domains. This task has the following subtasks:

  • Install 128-bit encryption software.

  • Establish trusts that are required for migration.

  • Establish migration accounts for your migration.

  • Configure the source and target domains for security identifier (SID) history migration.

  • Configure the target domain organizational unit (OU) structure.

  • Install ADMT in the target domain.

  • Specify service accounts for your migration.

Installing ADMT in the Target Domain

Planning to Restructure Active Directory Domains Between Forests

Specify and transition service accounts using either the Service Account Migration Wizard or ADMT command-line tools. You can use the admt service command-line tool to specify service accounts in the source domain. You can use the admt user command-line tool to transition service accounts that you specify.

Transitioning Service Accounts in Your Migration

Migrate global groups using either the Group Account Migration Wizard or the admt group command-line tool.

Migrating Global Groups

Migrate standalone managed service accounts, user accounts, and workstation accounts with their SID histories in batches. You can use either the User Account Migration Wizard or the admt user command-line tool to migrate user accounts. You can use the Managed Service Account Migration Wizard or admt managedserviceaccount command-line tool to migrate standalone managed service accounts. Group managed service accounts cannot be migrated.

Migrating Accounts While Using SID History

Migrating Managed Service Accounts

Migrating All User Accounts

Migrate resources, such as member servers and domain local groups. You can use either the Computer Account Migration Wizard or the admt computer command-line tool to migrate computer accounts. You can use the Group Account Migration Wizard or the admt group command-line tool to migrate groups.

Remigrating User Accounts and Migrating Workstations in Batches

Translate security on servers to add the SIDs of the user and group accounts in the target domain to the access control lists (ACLs) of the resources. You can use either the Security Translation Wizard or the admt security command-line tool.

Translating Security in Add Mode

Repeat a migration of user accounts, workstation computers, and member servers, including translating local user profiles to user and computer objects that you migrated earlier.

Remigrating User Accounts and Migrating Workstations in Batches

Migrate domain local groups using either the Group Account Migration Wizard or the admt group command-line tool.

Migrating Domain and Shared Local Groups

Migrate domain controllers.

Migrating Domain Controllers

Complete postmigration tasks. This task has the following subtasks:

  • Translate security on member servers.

  • Decommission the source domains.

Translating Security on Your Member Servers

Decommissioning the Source Domain