Cloud Platform generally creates a migration environment within 10-15 minutes. However, this process might take up to an hour or more, depending on the size of the Drupal 7 site’s database and files, and network traffic at that time.
This is an expected behavior. The migration environment needs to generate a new database on all of your environments, which stores the copy of the Drupal 7 database that will be used as the migration source. No other changes are being made to any of your environments. However, the UI does not return control until the migration environment is generated.
The file copy operation in Cloud Next takes longer as compared to Cloud Classic. This occurs because the files are first copied from the production environment to an intermediate ODE environment, and then to a migration environment. After the copy operation is complete, the system deletes the ODE environment, thereby keeping only the migration environment. This additional step in the migration process consumes more time.
This issue occurs when you have multiple concurrent requests in the database layer. In addition, you might have a complex infrastructure that results in high network latency.
To migrate your data, you can use the
drush ama:import command. Acquia
recommends you to not use the Acquia Migrate Accelerate web user interface, and
run Acquia Migrate Accelerate locally as it is now open source. For more
information, see AMA is now open source.