IPs Flashcards
What is for a public IP?
To identify the machine on the internet
2 machines can share the same public IP?
No, must be unique across the whole web
What is for a private IP?
To identify the machine only on a private network
2 machines can share the same private IP?
No in the same private network but 2 different private networks can have same IPs
What do use machines to connect to WWW?
using a NAT (Network Address Translation) + Internet Gateway (proxy)
You can use any private IP that is not in use?
No, only a specified range
How many Elastic IPs can you have on your account?
5, you can ask AWS to increase that
Can an instance public IP change?
Yes, when you stop and start it
What is an Elastic IP?
A fixed public IPv4 for your instance
Can you attach an Elastic IP to another instance?
Yes
It is a good decision to use an Elastic IP?
No, try to avoid it. They often reflect poor architectural decisions.
In terms of IPs, by default, your EC2 instance comes with?
1 private IP and 1 public IP
What IP can you use to SSH into your EC2 machine?
The public one, you can’t use private one because you are not in the same network
What can you use for communication between instances in the same VPC
private IPs, traffic between two EC2 instances going over the public internet incurs in high costs
