Other troubleshooting topics - Application Migration Service
Windows license activation – AWSMigration leaving behind replication volumes after cutoverReplication lag issuesWindows Driver changesWindows Dynamic Disk troubleshootingDeleting AWS MGN resourcesSet UEFI boot mode

Other troubleshooting topics

Windows license activation – AWS

AWS Application Migration Service converts the Windows OS licenses to AWS Windows licenses and activates them against the AWS KMS.

If license activation failed, follow this AWS guide to resolve.

Migration leaving behind replication volumes after cutover

If you are seeing left behind replication volumes in AWS after running the cutover process, then ensure that the names of the replication volumes match those given to them by AWS Application Migration Service (AWS MGN).

Most likely, you have a script running in your AWS account that renames Amazon EBS volumes to match the name of the EC2 instance they are attached to.

However, by renaming an EBS volume used by AWS MGN for replication you are severing its association with AWS MGN, and AWS MGN will not automatically clean up such volumes.

Replication lag issues

Potential solutions:

  • Make sure that the Source server is up and running.

  • Make sure that AWS MGN services are up and running.

  • Make sure that TCP Port 1500 is not blocked outbound from the source server to the replication server.

  • If the MAC address of the Source had changed, that would require a reinstallation of the AWS Replication Agent.

  • If the source machine was rebooted recently or the AWS Application Migration Service were restarted, the disks are re-read after this and until it’s finished, the Lag will grow.

  • If the source machine had a spike of write operations, the Lag will grow until AWS Application Migration Service manages to flush all the written data to the test or cutover instance replication server.

Windows Driver changes

Users may see changes in Windows drive letter assignments (for example, Drive D changed to E) on target machines launched by AWS Application Migration Service.

This happens because Windows sometimes re-configures the drive letters when a machine comes up on a new infrastructure, for example, if the Source server had a drive letter mapped to a disk that was not replicated (such as a network drive). You can solve this issue by remapping the drive letters on the test or cutover instance correctly after it has been launched.

Windows Dynamic Disk troubleshooting

Moving a Windows Dynamic Disk from a local computer to another computer may change the disk status to "Foreign", resulting in a disruption in replication. The solution is to import the foreign disk, as discussed in this Microsoft troubleshooting article.

Deleting AWS MGN resources

You can delete various AWS MGN resources, including source severs, jobs, and the replication settings template, through the MGN API. Use the following API commands to delete resources:

DeleteSourceServer

Use the DeleteSourceServer API command to delete source servers.

This command:

  • Deletes a single source server by ID.

  • Successful deletion should result in a 204 HTTP response code.

  • To delete source server the server should be in a DISCONNECTED or CUTOVER state. If the source server has not been cut over, you must first call the DisconnectFromService API and then call the DeleteSourceServer API.

DeleteJob

Use the DeleteJob API command to delete a Job.

This command:

  • Deletes a single Job by ID.

  • Successful deletion should result in a 204 HTTP response code.

  • Job must be in a COMPLETED state to be deleted.

DeleteReplicationConfigurationTemplate

Use the DeleteReplicationConfigurationTemplate API command to delete the replication template.

This command:

  • Deletes a single replication template by ID.

  • Successful deletion should result in a 204 HTTP response code.

  • All source servers and jobs must first be deleted before calling the DeleteReplicationConfigurationTemplate API.

Set UEFI boot mode

UEFI boot mode can only be used with Nitro based EC2 Instance types. Nitro requires ENA driver, which is only supported from kernel 3.10. If you are getting the following error: "Source server boot mode is UEFI which is inconsistent with target instance." It might be due to OS using old UEFI format, which was used up to kernel 3.8.

If this is the case you should set the source server boot mode to 'Legacy BIOS'.