What happens when I reboot an EC2 instance?

Question

When I reboot an EC2 instance, do I get the initial image again, or is the state of the hard disk before the reboot kept?

And what happens with billing, does the hour start again, or do I continue with the fraction of the hour I was in when I rebooted?

Answer 1

It is just like rebooting your PC. 

• The connected hard disk is not affected but the temporary RAM data is erased and your saved data is available just like your PC.
• Rebooting your instances do not have any effect on your billing.
• Only the time your instances are running is taken into account, and it is stopped as soon as you stop or terminate your instance.