#Windows server 2019 Upgrade the secondary domain controller to the primary domain controller

Table of contents

1. Implementation background

 2. Upgrade the auxiliary domain controller

1. On the Master, open AD Users and Computers and change the connected domain controller

2. Select Backup

 3. Select the current domain, right-click and select "Operation Host"

4. Check that fsmo has changed

5. Repeat steps 3-4 to modify the remaining PDCs and infrastructure hosts in turn

6. Continue to open the AD domain and trust relationship, right-click and select "Operation Host"

7. Register the architecture host component

8. Open the MMC console, add the AD schema in the add/delete snap-in and open it

9. In the now opened AD architecture, first connect to Backup, right-click and select "Operation Host"

3. Verification

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1. Implementation background

The customer is now going to migrate the domain controller. Currently, the auxiliary domain controller has been set up and added to the domain. Now the operation of upgrading the auxiliary domain controller is performed.

Primary domain controller: AD-Master IP: 172.16.89.253

Secondary domain controller: AD-Backup IP: 172.16.89.252

Pre-work:

Query the ownership of fsmo on the Master and Backup respectively before the upgrade

netdom query fsmo

Open Windows Powershell with administrator privileges

Master：

Backup：

 2. Upgrade the auxiliary domain controller

1. On the Master, open AD Users and Computers and change the connected domain controller

2. Select Backup

 3. Select the current domain, right-click and select "Operation Host"

select "yes"

4. Check that fsmo has changed

5. Repeat steps 3-4 to modify the remaining PDCs and infrastructure hosts in turn

6. Continue to open the AD domain and trust relationship, right-click and select "Operation Host"

7. Register the architecture host component

8. Open the MMC console, add the AD schema in the add/delete snap-in and open it

A snap-in to add to the AD schema

Right click in the Active Directory schema and select "Change Active Directory" domain controller

Select secondary domain controller server

9. In the now opened AD architecture, first connect to Backup, right-click and select "Operation Host"

Confirm current schema master by re-entering netdom query fsmo

Then repeat the above operation

3. Verification

View FSMO roles on primary and secondary domain controllers

At this point, the switch is completed, and the DNS of other hosts can be configured as the IP address of the auxiliary domain.