VPC Fundementals Flashcards
(29 cards)
What is a VPC?
A Virtual Private Cloud, a private network in AWS to deploy resources.
What is a subnet?
A partition of a VPC’s network; tied to an Availability Zone.
What is the difference between public and private subnets?
Public subnets can access the internet; private subnets cannot.
What component allows subnets to access the internet?
Internet Gateway for public subnets; NAT Gateway for private subnets.
What is an Internet Gateway?
Allows instances in a VPC to connect to the internet.
What is a NAT Gateway?
Allows instances in private subnets to access the internet while remaining unreachable from it.
What is a NACL?
A subnet-level firewall that allows or denies traffic.
What is a Security Group?
An instance-level firewall that only allows traffic.
How do NACLs and Security Groups differ?
NACLs are stateless and support DENY rules; Security Groups are stateful and support only ALLOW rules.
What is the purpose of VPC Flow Logs?
To capture information about IP traffic going to and from network interfaces in a VPC.
Where can VPC Flow Logs send data?
Amazon S3, CloudWatch Logs, or Kinesis Data Firehose.
What is VPC Peering?
A private connection between two VPCs using the AWS network.
Can VPC peering be transitive?
No, VPC peering is not transitive.
What is a VPC Endpoint?
Allows private access to AWS services from your VPC.
What are the two types of VPC Endpoints?
Gateway (for S3/DynamoDB) and Interface (for other services).
What is Site-to-Site VPN?
Encrypted VPN over the internet connecting on-premises to AWS.
What is AWS Direct Connect?
A private, fast, secure physical connection from on-premises to AWS.
Which connection goes over the public internet?
Site-to-Site VPN.
Which connection is private and takes longer to set up?
AWS Direct Connect.
What is a NAT Gateway used for?
Providing internet access to private subnets.
What are NACLs and where are they applied?
Network Access Control Lists applied at the subnet level.
What are Security Groups and where are they applied?
Instance-level firewalls applied to EC2 or ENI.
What are VPC Flow Logs used for?
Monitoring IP traffic and troubleshooting network issues.
Can you peer VPCs with overlapping CIDRs?
No, VPC peering requires non-overlapping CIDR blocks.
