VPC Flashcards
VPC. What does it mean. What is it.
Virtual Private Cloud.
It’s your own little bit of the AWS network.
VPC Limit Per Account
5 VPCs, per region, per account.
What’s a subnet?
Subnets allow you to split your VPC into networks.
True or false. Subjects must reside in the CIDR block of their parent VPC?
True
CIDR block means.
Classless inter domain routing.
True or false. Public subnets will have a public and private IP.
True.
For a subnet to be made public. You must carry out two action. What are they?
Add an internet gateway
Add a record to the routes table referring to said internet gateway.
The two types of subnet are.
Public
Private
IGW stands for?
Internet gateway.
True or false. To make a application highly available. Resources should be in subnets split across multiple AZ’s.
True.
All subnets have a default route that can not be deleted. It allows all the subnets to talk to each other. What is this route?
10.0.0.0/16
1st address in an AWS subnet is reserved for…
Network
2nd address in an AWS subnet is reserved for…
Routing
3rd address in an AWS subnet is reserved for…
DNS
4th address in an AWS subnet is reserved for…
AWS future use
Last address in an AWS subnet is reserved for…
Broadcasting
NACL stands for
Network access control list
What is the purpose of a NACL?
Network firewalls for subnets.
True or false. NACLs contain a numbered list of rules that run sequentially
True
What’s the purpose of a security group?
Firewall / access control at the resource level.
Security groups are state full. What doss this mean?
You don’t have to configure rules to allow for return traffic.
NACLs are stateless. What does this mean?
You will have to configure rules for how to handle return traffic.
What’s the purpose of a NAT gateway?
It allows resources from a private subnet to make requests out to the internet.
True or false. NAT gateways do not respond to incoming requests from the internet?
True.
Steps that must be taken to get a NAT gateway up and running?
Create the Nat gateway.
Add a route to the gateway in the routes table.
NAT gateway stands for.
Network Address Translator.
What’s the purpose in a bastion host?
It allows you to access subnets from external hosts.
Eg connect to an EC2 in a private subnet, from your home computer.
What resource is used to create a bastion host on AWS?
EC2
Keys to other servers should never be kept on a bastion server. How do you get around this?
SSH agent forwarding.
What does the transit gateway do?
It’s one hub that can centralise all data in all VPCs.
If your VPN decice DOES support BGP (Border Gateway Protocol) you should enable…
Dynamic routing