As was noticed in previous answer, AWS is required for using Bamboo in Cloud. It is however not necessary if you're running Bamboo server.
For server, there are more agent types to choose: local agents (run on the same machine as the server node), remote agents (usually run in the same local network), or elastic agents (on EC2 from AWS) - as an option, not necessity.
As per the below documentations, AWS is a fundamental requirement to use Bamboo Cloud:
Badges are a great way to show off community activity, whether you’re a newbie or a Champion.Learn more
Bamboo 5.9 will no longer be supported after June 12, 2017. What does this mean? As part of our End of Life policy, Atlassian supports major versions for two years after the first major iteratio...
Connect with like-minded Atlassian users at free events near you!Find a group
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no AUG chapters near you at the moment.Start an AUG
You're one step closer to meeting fellow Atlassian users at your local meet up. Learn more about AUGs