Do migrate module migrations continue in background if terminal session ends? I'm working on a migration that involves some long migration times - many hours to migrate some tables. I use the drush commands to perform my migrations, but often something happens in the middle. The window closes by accident, or I lose my Internet connection for a minute, whatever. When I open a new terminal and run 'drush ms' I see my migration marked "importing"... but is it really going to finish at some point?
I believe not. That is why Migrate supports a reset option migrations if they are orphaned or otherwise fail. Typically you run migrations as a shell user (yourself) on the system. Unless you're using something else to keep your processes alive -- they die when the terminal they're connected to die.