Elastic Load Balancing & Auto Scaling Groups Flashcards
Vertical scalability
Increase size of the instance
Vertical scalability is common for…
non-distributed systems, such as a DB
Example of vertical scalability. t2.micro becomes…
t2.large
Horizontal scalability
Increase number of instances for an application
Horizontal scaling implies…
Distributed system
High availability
Running application or system in at least 2 AZ’s
Elasticity
Auto-scaling capabilities. (Cloud friendly)
Agility
Reduce time to make resources available
Load balancers
Servers that forward traffic to multiple servers
Why use a load balancer?
Spread load
Single domain name
Handle failures
Perform health checks
SSL Termination
HA across zones
ELB
Managed load balancer
Application Load Balancer OSI Layer
Layer 7 HTTP/HTTPS/gRPC
Network Load Balancer
Gateway Load Balancer
Layer 4
High performance
Static IP
Gateway Load Balancer
GENEVE Protocol (Layer 3)
Route traffic to firewalls, 3rd party virtual security appliances.
IDS/Deep packet inspection
ASG scale out
Add instances
ASG scale in
Remove instances
ASG acronym
Auto scaling group
ASG goals
Scaling
Ensuring minimum and maximum machines running
Automatically register instances to a LB
Replace unhealthy instances
Financial benefit of ASG
Run at optimal capacity
Manual scaling
Update ASG size manually
Dynamic scaling
Scale automatically
Simpte/Step scaling
Performance thresholds for ASH to take action
Target tracking scaling
Automatic scaling to a target number
Scheduled scaling
Schedule scaling at certain times
Predictive scaling
Machine learning used to predict scaling. Automatic scaling
