AWS Services Summary - Compute

Audience

Me

EC2

Storage/Disk

Instance Store volume: a temporary block-level storage for EC2 instances

Monitoring

Default metrics:

• CPU
• Network/Bandwidth, Read/Write bytes

Not-ready metrics:

• Memory, Disk I/O:
  • Memory utilization
  • Disk swap utilization
  • Disk space utilization
  • Page file utilization
  • Log collection

Install metrics:

• Memory, Disk I/O: Install the Amazon CloudWatch agent to all the EC2 instances. View the custom metrics in the CloudWatch console.

Dynamic scaling policy

Types: Simple scaling

• Based on CloudWatch alarm.
• Choose 1 action to conduct.
• Scale-in operation depends on CloudWatch alarm.

Target tracking policy

• Based on CloudWatch & built-in metrics (i.e Averge CPU Utilization). CloudWatch metrics must be available or defined.
• Scale (in/out) operations trigger by calculating the current resources utilization that matches the defined target metric.
• Faster scale-in operation.

Step scaling

• It is a Simple scaling with various actions.
• Apply multiple actions for a scaling events.
• Allow scaling operation more smoothly and optimized.

Scale-In Mechanism

Auto Scaling services choose below critiria to perform terminate EC2 instances

Priority:

1. AZ has the most VMs
2. Oldest launch templates (lowest version)
3. Closet to next billing hour
4. RANDOM if can’t decide more.

Operation

Take snapshot & restore

Annotations:

• Source instance to take snapshot: instance A
• Destinated instance to perform restore: instance B

Steps:

• Take snapshot of a running instance A’s volumes. We have snapshot A
• Create a new volume from snapshot A. We have volume A
• On the target instance B, shutdown the instance.
• Force detachment on the volume B of instance B. Then delete the volume if not use anymore
• Attach the new volume A to instance B.
• Start instance B.
• Verify the instance B with new snapshot snapshot A

Load Balancer

Application Load Balancer

Main features

• Layer-7 OSI load balancer
• Can not assign Elastic IP

Network Load Balancer

• Layer-4 OSI load balancer
• Can assign Elastic IP