NAT Gateway/NAT Instance

Question 1

What is a NAT Gateway?

Answer 1

This is an AWS NAT managed service.

Question 2

What is the maximum number of NAT Gateways that can be attached to an Availability Zone?

Answer 2

5

Question 3

What is the throughput of one NAT Gateway?

Answer 3

5 Gbps and automatically scales to 100 Gbps

Question 4

What are two ways to enable private addresses within a vpc to communicate out to the internet?

Answer 4

1) Use the AWS NAT Gateway
2) Create a NAT EC2 instance

Question 5

What type of NAT device does AWS recommend using for natting?

Answer 5

AWS NAT Gateway service

Question 6

What does a NAT instance run on?

Answer 6

It runs on an EC2 instance.

Question 7

Traffic destined for a NAT instance is actually destined for the EC2 instance that it’s running on. If the the source/destination check is enabled on the EC2 ENI, what will happen to the traffic?

Answer 7

It will be dropped.

Question 8

Which NAT service is EOL?

Answer 8

NAT EC2 Instance

Question 9

When configuring HA for NAT Instances, how is that managed?

Answer 9

NAT instances HA would require configuring a separate EC2 instance in the public subnet and have scripts that would update the routing table if one subnet is unavailable. Unlike NAT Gateways, this is a self-managed service.

Question 10

How is HA managed for NAT Gateways?

Answer 10

NAT Gateways HA would require configuring a separate gateway in the different public subnets, but HA is managed by AWS. This is an AWS managed service so there’s no additonal configuration needed.

Question 11

True or false: One NAT Gateway can provide HA in one region.

Answer 11

False: NAT Gateways are only highly available in the availability zone it is running from.

Question 12

What are the two charges associated with NAT Gateways?

Answer 12

1) Hourly use charge; pricing differs from different regions
2) Data processing charge (how much data goes through the NAT gateway)

Question 13

What type of ip does a NAT Gateway use to route to the internet?

Answer 13

Elastic IP

Question 14

What are two ways to route traffic from your NAT Gateway to on-prem network?

Answer 14

1) Transit Gateway
2) Virtual Private Gateway

Question 15

What are the two types of NAT Gateway?

Answer 15

1) Private NAT Gateway
2) Public NAT Gateway

Question 16

A NAT Gateway can scale up to 100Gbps, but if more bandwidth is needed, what is the best approach?

Answer 16

Split resources into separate subnets and configure a NAT Gateway for each subnet.

Question 17

How many packets per second can a NAT Gateway process?

Answer 17

1 million packets per second

Question 18

How many packets per second can a NAT Gateway scale up to?

Answer 18

10 million packets per second

Question 19

By default, how many elastic ips can be configured on a NAT Gateway?

Answer 19

2

Question 20

If you delete the private NAT Gateway, will the private ip address persist?

Answer 20

No, it will also be deleted.

Question 21

You are configuring an EC2 instance that would need to access resources in the internet, which will include a NAT Gateway. You will be implementing security measures with both security groups and a NACL. You plan on configuring the security group on the NAT Gateway and NACL on the IGW. Will this design work?

Answer 21

Yes, but NAT Gateways cannot have a security group, only the ENI of the EC2 instance.

Question 22

What are three AWS connectivity services that cannot use NAT Gateway?

Answer 22

1) VPC peering
2) Site-to-Site VPN
3) Direct Connect

Question 23

In process
What are the steps to configure a NAT Gateway for a private subnet to access resources on the internet?