EC2

Question 1

EC2 Instance Metadata

Answer 1

allows your EC2 instances to learn about themselves and they don’t have to use an IAM role for that purpose.

Question 2

EC2 Instance Metadata URL

Answer 2

http://169.254.169.254/latest/meta-data

This IP 169.254.169.254 is an internal IP to AWS, it will not work from your computer, it will only work from your EC2 instances, and using this, you can retrieve the IAM role name from the Metadata, but you cannot retrieve the IAM policy

The only way to test the IAM policy is to use the policy simulator or the dry run options. But we cannot retrieve the content of the IAM policy, using this URL.

Question 3

get instance ID

Answer 3

curl http://169.254.169.254/latest/meta-data/instance-id

when you curl parts of the url - you can see what meta-data you can find out. So start with

curl http://169.254.169.254/latest/meta-data

and navigate from it

Question 4

You would like to have the same data being accessible as an NFS drive cross AZ on all your EC2 instances. What do you recommend?

Answer 4

mount an EFS

EFS is a network file system (NFS) and allows to mount the same file system on EC2 instances that are in different AZ

Question 5

You would like to have a high-performance cache for your application that mustn’t be shared. You don’t mind losing the cache upon termination of your instance. Which storage mechanism do you recommend as a Solution Architect?

Answer 5

Instance Store

Question 6

You are running a high-performance database that requires an IOPS of 210,000 for its underlying filesystem. What do you recommend?

Answer 6

EC2 instance store

Is running a DB on EC2 instance store possible? It is possible to run a database on EC2. It is also possible to use instance store, but there are some considerations to have. The data will be lost if the instance is stopped, but it can be restarted without problems. One can also set up a replication mechanism on another EC2 instance with instance store to have a standby copy. One can also have back-up mechanisms. It’s all up to how you want to set up your architecture to validate your requirements. In this case, it’s around IOPS, and we build an architecture of replication and back up around i