Third post in our AWS Solutions Architect Associate certification preparation series. Hope you have enjoyed the first post and the second in the series. We have a few more topics to cover in this series and some of them are in this post.
[ Disclaimer : This is not a complete training material for the certification. This is just random (short) notes which we captured from course curricula, which will help the readers for their final revision/rewind before appearing for the exam. We do not offer any guarantee in passing the exam with this content ]
EBS (Elastic Block Storage)
General Purpose (SSD) (GP2) – General purpose, cost-effective storage. 100 – 16000 IOPS. Mixed workload
Provisioned IOPS (SSD) (IO1) – For IO intensive workloads.
Throughput Optimized HDD (ST1) – low cost magnetic storage, performance in terms of throughput.
Cold HDD (SC1) – For large, sequential cold-data workloads.
Magnetic – Uses magnetic storage, for infrequently accessed data.
migrating a EC2 instance from one region to other ::> Create a snapshot of the root volume > Create an AMI from the snap > Create an instance from AMI on another region.
snapshots are existing in S3.
——————- advertisements ——————-
AMI (Amazon Machine Images) can also be copied to another region for VM deployments.
When you delete/terminate an instance, the additional drives won’t get deleted by default.
For AMIs backed by EBS volumes, the OS root device is created on an EBS snapshot of an EBS volume.For AMIs backed by instance store, the instance root device is created from a template stored in AWS S3.
Instance store root volumes will not be listed in EC2>EBS>Volumes as this is not an EBS volume. we can create the instance from an instance store, but only to limited hardware (instance type) selection. We can not stop an instance which is running on instance store. Only reboot or terminate options are available. If there’s an issue in the underlying hardware, data will be lost. It is also called Ephemeral (short time).
Root volume (of the instance) can be encrypted by ::> create a snapshot of the root volume> copy it by encrypting it> create an AMI from the encrypted copy> launch an instance from it.
Cloudwatch and Cloudtrail :
Cloudwatch (Gym trainer to remember) is for performance monitoring – Compute (EC2,Route53,ELoadbalancers..) ,Storage (EBS Volumes, Storage gateway) and CDN (CloudFront)
Cloudtrail (CCTV to remember) is for checking who is calling for who (kind of access logging in my understanding)
Cloudwatch monitors 5minute intervel by default, can be reduced to 1minute also.
2 ways of accessing the AWSCLI, 1 is giving the user the permissions required for CLI and using the credentials in the CLI. Second one is by creating the IAM role for CLI access and adding that to the EC2 instance.
——————- advertisements ——————-
Sample commands :
aws s3 ls (to list the S3 buckets)
aws s3 mb s3://bforumnewbucket (to create a bucket with the given name. mb=make bucket)
credentials are saved in plain text in ~/.aws directory.
curl http://169.254.169.254/latest/meta-data – Captures any meta data about the instance
curl http://169.254.169.254/latest/user-data – captures bootstrap data
EFS (Elastic File System)
supports NFSv4. Pay as you use. Petabyte scale. Thousands of concurrent NFS connections. Read after write consistency.
clustered placement group :- for High performance computing, requiring high thruput or low latency. Within a single AZ.
Spread placement group :- for applications with small number of critical instances, that should be kept seperate. Can span across AZs.
Placement groups names must be unique.
That is another short post, many more topics to come. Hope you are enjoying this series. Your feedbacks will help in improving our contents, please feel free to add in the comments section.