Custom VPC

Question 1

What is the domain of VPCs (global, region, AZ)?

Answer 1

it is regional and it is isolated.

Question 2

Is VPC a resilient service by default?

Answer 2

Yes.

Question 3

Where does a VPC operate?

Answer 3

Operates from all AZs in that region where it is created.

Question 4

Can you have multiple isolated VPCs in the same region for the same account?

Answer 4

Yes

Question 5

What is the default configuration for IN and OUT traffic in VPCs?

Answer 5

Nothing IN or OUT of a VPC without explicit configuration

Question 6

What is the default blast redius of a VPC?

Answer 6

Any problems are limited to that VPC or anything connected to it.

Question 7

What means that VPC has a flexible configuration?

Answer 7

It can be configured to have simple or multi-tier networks.

Question 8

Does VPC allow hybrid networking?

Answer 8

Yes, it allows connection to other cloud or on-premises networks.

Question 9

Does VPC support “Dedicated tenancy”? and what does it mean?

Answer 9

Yes, it means that the hardware where the VPC runs is dedicated to you.

Question 10

When can you choose between default or dedicated tenancy?

Answer 10

During the VPC creation.

Question 11

Is the dedicated tenancy a default we should choose? and why?

Answer 11

Not by default because it comes with a premium price. Only choose when really needed.

Question 12

What is mandatory to create a VPC?

Answer 12

To assign a CIDR range (min /28, max /16)

Question 13

Can secondary CIDR ranges be added after the VPC is created?

Answer 13

Yes, you can add a maximum of 5 more ranges.

Question 14

Is the limit of 5 CIDR blocks per VCP a hard or soft limit?

Answer 14

It is a soft limit that can be increased by creating an AWS support ticket.

Question 15

Can you choose what IPv6 range to use in a VPC?

Answer 15

Yes, you can use your own IPv6 that you own.

Question 16

When AWS allocates an IPv6 range, can you choose which one it will be?

Answer 16

No, when the range is allocated by AWS you have no choice on which range to use.

Question 17

Does IPv6 have public and private addresses?

Answer 17

No, all are public.

Question 18

How are IPv6 addresses routed by default (as public or private)?

Answer 18

they are routed as public addresses by default.

Question 19

Using IPv6 addresses means lower or higher overhead?

Answer 19

Lower.

Question 20

What is the default DNS address by default in a range?

Answer 20

VPC + 2.

Example: 10.0.0.0 –> 10.0.0.2 is the DNS IP

Question 21

What main options over DNS can be configured in VPC?

Answer 21

1. Edit DNS hostnames - with function ‘enableDnsHostnames’

2. Edit DNS resolution - with function ‘enableDnsSupport’

Question 22

What means that enableDnsHostnames function is enabled?

Answer 22

Instances with public IPs in a VPC are given public DNS hostnames

Question 23

What means that enableDnsSupport function is enabled?

Answer 23

Instances in the VPC can use the DNS IP address