Setup ScyllaDB with mTLS for node to node communication

[mflendrich]

Issue originally authored by tnozicka as #1217

Is this a bug report or feature request?

• Feature Request

What should the feature do:
We need to setup ScyllaDB with node to node mTLS to make sure the node communication on our shared platform is encrypted and authenticated.

This also prevents nodes to accidentally join a different cluster which can happen when there is no authentication and IPs are eventually reused. (If dc name matches.)

We should enable node-to-node encryption by default and only have fallback option to use insecure one instead.

https://docs.scylladb.com/stable/operating-scylla/security/node-node-encryption.html

[mflendrich]

@zimnx can you confirm that this is not done?

If done -> close as completed
If not done -> unassign yourself and set status to "Triaged: In Freezer" or have a conversation why we should do this very soon

Thanks!

[zimnx]

it's not done, issue is already in required status.