There has always been a need to synchronize address books (GAL) between companies in scenarios such as M&A, affiliated companies, or group companies, where using a single tenant is not possible. Traditionally, this was achieved by setting up servers like Microsoft Identity Manager (MIM) on an On-Premise Exchange Server, creating objects between ADs to synchronize address books. Alternatively, it could be implemented through HR integration solutions.
However, adopting MIM or HR integration solutions can be prohibitively expensive and requires specialized knowledge for management, making it very burdensome.
Recently, it has become possible to synchronize address books with Cross-tenant Synchronization. Specifically, this functionality automates the invitation of Guests.
Step 3: Automatically redeem invitations in the target tenant
Trust settings > Automatically redeem invitations with the tenant [Tenant Name] > Check > Save
Step 4: Automatically redeem invitations in the source tenant
Entra Admin Center > External Identities > Cross-tenant access settings
Add organization
Enter Target Tenant ID > Add
Outbound access > Inherited from default
Trust settings > Automatically redeem invitations with the tenant Fabrikam > Check > Save
Step 5: Create a configuration in the source tenant
Cross-tenant synchronization
Configurations > New configuration
Specify the configuration name. > Create
Step 6: Test the connection to the target tenant
Get started
Provisioning Mode: Automatic > Admin Credentials > Tenant Id: Target Tenant ID > Test Connection > Save
Step 7: Define who is in scope for provisioning (Source Tenant)
Provisioning > Settings > Confirm Scope > Sync only assinged users and groups:
This means specifying only certain users or groups to synchronize.
Users and groups-> Add user/group
None Selected
Specify the target. > Select > Assign
Step 9: Review attribute mappings
If, for various reasons, you do not want to synchronize specific attributes, proceed as follows.
Provisioning > Mappings > Provision Microsoft Entra ID Users
You can remove some items except for the required fields.
Step 10: Start the provisioning job
Start provisioning
Target Tenant > Entra admin center > Users > All Users
You can verify that they are added as guests as shown below.
You can also verify this in the Exchange Admin Center as shown below.
You can also verify this in the address book as shown below.
Tenant-to-tenant synchronization settings are configured as follows: In the Source Tenant, set up the Outbound settings, and in the Target Tenant, set up the Inbound settings. This synchronization process results in Guest accounts. Since Guest accounts have Mail User attributes, they can be verified in the address book.
I am starting my blog in English for the first time.
The purpose is to make it easier to use commands or scripts provided in the videos on YouTube.
The topic for this week is Cross-tenant Mailbox Migration.
I have carried out the process in the simplest Only Cloud environment, and I will cover Azure AD Sync and Exchange Hybrid scenarios later. To understand the principles of Migration, you need to understand the principles of Migration in Exchange Server. I will update this part later.
Create Organization Relationship for the Source Tenant
$targetTenantId="[tenant id of your trusted partner, where the mailboxes are being moved to]"
$appId="[application id of the mailbox migration app you consented to]"
$scope="[name of the mail enabled security group that contains the list of users who are allowed to migrate]"
$orgrels=Get-OrganizationRelationship
$existingOrgRel = $orgrels | ?{$_.DomainNames -like $targetTenantId}
If ($null -ne $existingOrgRel)
{
Set-OrganizationRelationship $existingOrgRel.Name -Enabled:$true -MailboxMoveEnabled:$true -MailboxMoveCapability RemoteOutbound -OAuthApplicationId $appId -MailboxMovePublishedScopes $scope
}
If ($null -eq $existingOrgRel)
{
New-OrganizationRelationship "[name of your organization relationship]" -Enabled:$true -MailboxMoveEnabled:$true -MailboxMoveCapability RemoteOutbound -DomainNames $targetTenantId -OAuthApplicationId $appId -MailboxMovePublishedScopes $scope
}
New-MailUser -MicrosoftOnlineServicesID User01@tailspintoys.kr -PrimarySmtpAddress User01@tailspintoys.kr -ExternalEmailAddress user01@wingtiptoys.kr -Name User01 -DisplayName User01 -Alias User01
Set-MailUser -Identity User01 -EmailAddresses @{add="X500:Type the LegacyExchangeDN"} -ExchangeGuid "Type the ExchangeGuid"
#In scenarios where the existing domain needs to be completely removed, enter the onmicrosoft.com address and designate it as the target delivery domain.
Set-MailUser -Identity User01 -EmailAddresses @{add="smtp:user01@M365x47686041.onmicrosoft.com"}
The attributes were created to map as follows.
Check the migration connection status with the following command.
