Module 2 of 6 β’ Network Cards & Outbound Translation
Elastic Network Interfaces (ENI) & NAT Gateways
Explore the two building blocks that confuse most cloud newcomers:
1) What is an ENI (and why do IP addresses and Security Groups belong to the ENI instead of the server?), and
2) How does a NAT Gateway let private servers talk to the internet while blocking strangers from coming back in?
πͺͺ
Two Simple Analogies:
An ENI is like a removable SIM card & security badgeβif your phone breaks, you unplug the SIM card and plug it into a backup phone, and calls to your number immediately ring the backup phone!
A NAT Gateway is like a hotel front-desk conciergeβwhen a VIP guest in a secret room mails a package out, the concierge puts the hotel's front-desk address as the return address and only forwards expected replies back to the VIP's room.