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Ephemeral disk is the disk that is created with an instance. Any changes made to it while to its contents continue to exist when the instance is running paused, suspended, shutdown or rebooted. Any changes are lost when the instance is terminated [ does rebooting cause ephemeral disk to be lost? ]terminated.
What boot images are available?
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How do I start and stop an instance?
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Each instance displayed on the Horizon dashboard has a drop down menu associated with it at the far right of the screen. It has options to Pause, Suspend or Terminate the instance. Pausing an instance stores its state in memory while suspending it writes that state information to disk. Terminating an instance deletes it and gets rid of its state information including its ephemeral disk. If an instance has been paused or suspended it can be restarted by selecting Resume from the menu. If an instance has been terminated a new instance needs to be created, the old one cannot be recovered.
Rebooting an instance
A soft reboot attempts a graceful shutdown and restart of the instance, a hard reboot power cycles the instance.
How can I back up my instance?
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How do I get access to more resources (core/memory/disk)?
What are volumes?
A volume is a detachable block storage device, similar to a USB hard drive. You can attach a volume to only one instance. The contents of a volume are not lost when the instance it is attached to is terminated.
How do I set up volumescreate a volume?
How do I boot from a volume?
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