EC2 Flashcards
What is AMI?
An AMI (Amazon Machine Image) is a template that contains the software configuration (operating system, application server, and applications) required to launch an EC2 instance
Permissions required on the private key (pem file)
0400
Default policy for inbound traffic in a security groups
Deny all
Default policy for outbound traffic in a security group
Allow all
What is an Elastic IP?
a static public IPv4 IP designed for dynamic cloud computing.
are Elastic IPs region specific or global?
region specific
command used to start services in an Amazon Linux 2 machine
systemctl
Whats bootstrapping?
Launching commands when the machine starts
what user is used to run the bootstrap routine?
root
What is the EC2 User data?
Data used to perform common automated configuration tasks and even run scripts after the . EC2 instance starts
What types of used data can you pass to Amazon EC2?
shells scripts and cloud-init directives
When are the user data scripts run?
By default they are only run during the boot cycle when you first launch an EC2 instance
Where is the user data script copied to for execution?
it is copied to the directory /var/lib/cloud
Why should you delete the user data script from the EC2 instance?
If you were to create an AMI from the EC2 instance and the user data was not deleted, then the script would be executed for every EC2 instance created from the resulting AMI
You pay for an EC2 instance compute component only when it’s in “running” state or also when it is on “stopped” state?
Only when it is in “running” state
Security Groups can reference all of the following except:
- IP address
- CIDR block
- Security Group
- DNS name
DNS name
What security groups are locked down to?
- a region
- a vpc
- a region/vpc combination
a region/vpc combination
What does EC2 stand for?
Elastic Compute Cloud
EC2 Instance Purchasing Options
- On-demand instances
- Reserver Instances
- Scheduled Instances
- Spot instances
- Dedicated Hosts
- Dedicated Instances
- Capacity Reservations
What is an on-demand instance?
it is an EC2 instance purchasing option where you pay bay the second for the instances that you launch
Whats is a Reserved Instance?
EC2 instance purchasing option where you pay for a term from one to three years
What is a Scheduled Instance?
EC2 instance purchasing option where the instance are always available on the specified recurring schedule, for a one-year term
What is a Spot instance?
EC2 instance purchasing option where you request unused EC2 instances
Whats a dedicated host?
EC2 instance purchasing option where you pay for a physical host that is fully dedicated to run you EC2 instances
