Actions during migration

Once the AWS Replication Agent is installed and data replication is active, you can perform the following actions on your source servers. These actions allow you to monitor replication health, manage the replication process, and progress through the migration lifecycle.

Start data replication

Data replication begins automatically after the AWS Replication Agent is installed. However, if replication has been paused or stopped, you can restart it manually.

To start data replication:

1. Open the AWS Transform MGN console and navigate to the Source servers page.

2. Select the checkbox next to one or more source servers.

3. Choose Replication, then choose Start data replication.

Pause data replication

You can pause data replication for a source server. When replication is paused, the replication server in the staging area is stopped, which reduces costs. Data changes on the source server are not replicated while replication is paused.

To pause data replication:

1. Open the AWS Transform MGN console and navigate to the Source servers page.

2. Select the checkbox next to one or more source servers.

3. Choose Replication, then choose Pause data replication.

Important

Pausing replication will cause lag to accumulate on the source server. When replication is resumed, a resync will be required to bring the target up to date. This may extend the time needed before the server is ready for cutover.

Resume data replication

After pausing replication, you can resume it at any time. AWS Transform MGN will perform a resync to replicate any data changes that occurred while replication was paused.

To resume data replication:

1. Open the AWS Transform MGN console and navigate to the Source servers page.

2. Select the checkbox next to one or more source servers.

3. Choose Replication, then choose Resume data replication.

Launch test instance

Once the initial sync is complete and the server reaches the Ready for testing state, you can launch a test instance. A test instance is a non-disruptive launch that allows you to validate the migrated server in AWS without affecting the source server or the ongoing replication.

To launch a test instance:

1. Open the AWS Transform MGN console and navigate to the Source servers page.

2. Select the checkbox next to one or more source servers in the Ready for testing state.

3. Choose Test and cutover, then choose Launch test instances.

4. Review the launch summary and choose Launch.

Note

Launching a test instance does not stop replication. Data continues to replicate from the source server while the test instance is running.

Finalize test and mark as ready for cutover

After validating the test instance, finalize the test to mark the server as ready for cutover. This action terminates the test instance and advances the server's migration lifecycle state.

To finalize a test:

1. Open the AWS Transform MGN console and navigate to the Source servers page.

2. Select the checkbox next to one or more source servers.

3. Choose Test and cutover, then choose Finalize test.

4. Confirm the action by choosing Finalize test in the dialog.

Launch cutover instance

When you are ready to perform the final migration, launch a cutover instance. Before launching a cutover instance, stop all services on the source server to ensure that no new data changes occur and that the replication lag is zero.

To launch a cutover instance:

1. Confirm that the data replication lag is zero on the source server.

2. Stop all operational services on the source server.

3. Open the AWS Transform MGN console and navigate to the Source servers page.

4. Select the checkbox next to one or more source servers in the Ready for cutover state.

5. Choose Test and cutover, then choose Launch cutover instances.

6. Review the launch summary and choose Launch.

Important

Launching a cutover instance is a significant step in the migration process. Ensure that you have completed all acceptance testing and that your team is prepared for the cutover window before proceeding.

Monitor replication health

You can monitor the replication health and progress of each source server from the AWS Transform MGN console. The Source servers page displays the current data replication state and migration lifecycle state for each server.

To view detailed replication information for a source server:

1. Open the AWS Transform MGN console and navigate to the Source servers page.

2. Choose the source server name to open the Server details view.

3. Review the Migration dashboard section to see the current lifecycle state, data replication status, and any alerts or errors.

The following data replication states may be displayed:

• Initial sync – The agent is performing the first full replication of the source server's data to AWS.

• Healthy – Replication is active and up to date with no lag.

• Lagging – Replication is active but behind the source server. This is typically a temporary state.

• Stalled – Replication has stopped due to an error. Review the alerts and take corrective action.

• Paused – Replication has been manually paused.

• Disconnected – The agent on the source server has lost connectivity to AWS Transform MGN.