Help:Suspending instances

If you need to stop activity on a given instance and do not want to destroy it, you can either suspend or pause it.

Pausing an instance is similar to putting your laptop to sleep, the instance state remains in memory:

root@cloudcontrol1003:~# OS_PROJECT_ID=project openstack server pause servername
root@cloudcontrol1003:~# OS_PROJECT_ID=project openstack server unpause servername

Suspending an instance is akin to hibernation, where the contents of the instance state is written to disk:

root@cloudcontrol1003:~# OS_PROJECT_ID=project openstack server suspend servername
root@cloudcontrol1003:~# OS_PROJECT_ID=project openstack server resume servername

Depending on how long the instance remains in paused/suspended state, it's possible the SSH sessions will resume working once the instance is reactivated due to SSH session timeouts not being reached. It really depends on your SSH client configuration.

IMPORTANT: A user can reactivate a paused/suspended instance by simply rebooting it. If you really want to ensure the instance is not reactivated by the user, you will need to disable their account.