Networks Flashcards
(127 cards)
AWS PrivateLink
AWS PrivateLink provides private connectivity between virtual private clouds (VPCs), supported AWS services, and your on-premises networks without exposing your traffic to the public internet. Interface VPC endpoints, powered by PrivateLink, connect you to services hosted by AWS Partners and supported solutions available in AWS Marketplace.
VPC Peering Connection
A VPC peering connection is a networking connection between two VPCs that enables you to route traffic between them using private IPv4 addresses or IPv6 addresses. You can create a VPC peering connection between your own VPCs, or with a VPC in another AWS account. The VPCs can be in different Regions (also known as an inter-Region VPC peering connection).
AWS DirectConnect
Dedicated connection to the AWS network
Gateway Endpoints
- Provides private access to the supported services.
- Can access public services (S3 and DynamoDB) from private VPC.
- Operates at VPC level, not subnet!
- Target specific routes
- Is highly available
- Is not billed for S3 access
- Use Amazon S3 public IP addresses
- Does not allow access from on premises
- Does not allow access from another AWS Region
Interface Endpoints
- Provides private access to the supported services.
- Operates at subnet level
- Target specific DNS names
- Have associated costs to access S3 bucket
- Use private IP addresses from your VP to access Amazon S3
- Allow access from on premises
- Allow access from a VPC in another AWS Region using VPC peering or AWS Transit Gateway
FSx
Windows file services. Resilient and highly available
Can be deployed in single or multi AZ mode.
Full range of backups
Accesible via VPC, Peering, VPN, Direct Connect
Transit Gateway
- AWS Transit Gateway connects your Amazon Virtual Private Clouds (VPCs) and on-premises networks through a central hub.
-Transit gateways are local devices and only can be associated with the VPCs in the same region (can be peered with the TG in other regions). - TG can connect directly to the user VPN gateway
- Is transitive capable device
Security Group
- Applied to the instance/service interface
- Is stateful
- Only contains ALLOW rule
- Can filter traffic between instances in the same subnet
Network ACL
- Applied at the subnet level
- Not stateful
- Can contain ALLOW and DENY rules
- Filter traffic entering on leaving subnet
ENI
Elastic Network Interface
- Primary ENI is attached to the instance and cannot be detached
- ENI only have private IPs
- Private IP address is assigned automatically and stays same during the lifetime of instance
- Public IP is not visible to the OS
- Public IP is not static, it can change after instance restart
- IPv6 is visible to the OS because it is publically routable
Elastic IP
Static public IP allocated per 1 private IP
SR-IOV
Single Route IO virtualisation. Allows many VMs share single NIC without impacting performance
- NICs are virtualisation-aware and can create multiple “virtual functions” NICs (cut down version) inside physical NIC
- 1 Physical NIC can support up to 256 virtual functions
- VM can communicate with the VF directly avoiding Hypervisor.
5-Tuple
5 Tuple- SRC IP, DST IP, SRC Port, DST Port, Protocol.
- Considered as “single flow”
- 5Gbps max for single 5 Tuple flow. Applies to the traffic between regions.
- Same region- physical limits of NIC e.g. 10 or 100Gbps
MPTCP
Multi Path TCP. Protocol to use many streams of TCP which is presented to the application as single stream.
EFA
Elastic Fabric Adapter
- Type of NIC on EC2
- Allows OS bypass, is used on HPC or ML (machine learning) applications
- HPC/ML application which use MPI or NCCL (???) are candidates for EFA
- Single subnet only, cannot be routed, security group should have “allow all” self reference inbound and outbound
Placement Groups
How physically close instances are placed.
- Cluster (keep instances together). Should be placed in the same AZ. Same rack and/or same host. Can achieve 10Gbps per stream instead of 5Gbps per stream.
- Spread (keep instances separated). Each instance runs in separate rack. 7 instances per AZ.
- Partition (spread groups of instances apart). More than 7 instances per AZ. max 7 partitions.
R53 Public Hosted Zone
Public zone is accessible from the internet, VPC can use public resolver via R53 endpoint on VPC +2 IP addressess
R53 Private hosted Zone
Associated with particular VPC, is not accessible from public Internet
CNAME record
Maps name to the another name. Cannot be used on “naked/apex domain” (e.g. kestasli.click). To solve this, ALIAS record should be used.
ALIAS record
Maps name to AWS resource. Can be used for naked or normal records. Default to pick ALIAS if AWS resources are used
Classic Load Balancer (CLB)
V1, Not really L7 device, can only use 1 SSL certificate per LB
Application Load Balancer (ALB)
- V2, L7 aware device, HTTP/S/WebSockets. Requires 8+ free IP addresses per subnet. /27 is minimal subnet size (/28 is absolute minimum).
- ELB is a DNS A Record pointing at 1+ Nodes per AZ
- EC2 doesn’t need to be public to work with a LB
Network Load Balancer (NLB)
- V2, Can balance TCP, TLS, UDP. Requires 8+ free IP addresses per subnet. /27 is minimal subnet size (/28 is absolute minimum).
- ELB is a DNS A Record pointing at 1+ Nodes per AZ
- EC2 doesn’t need to be public to work with a LB
CrossZone Load Balancer
Feature which allows LB to distribute load across all Availability Zones. Otherwise load can be distributed unequally if e.g. one AZ runs more EC2 instances. For Application Load Balancer this is enabled by default.