How do I open a port (e.g. 443) for my server?

Traffic to your server is controlled by security groups:

1. Go to Networking → Security Groups.
2. Add an inbound rule for the port and protocol, e.g. TCP 443 from 0.0.0.0/0.
3. Make sure the group is assigned to your server.

Rules are stateful (replies are allowed automatically), multiple groups add up, and changes apply immediately. Also check the firewall inside your operating system.

📖 Full guide: Managing security groups