AWS CSA Prep 3

Storage services overview 

S3 (Simple Storage Service) - It is an unlimited object storage (Key-Value). Can be used for static website hosting too (needs coupling with Route 53). Designed for 11 nines (99.999999999%) durability and 99.99 % availability. Charges are based per Gib storage as well as the data sent out of the region. Same region data transfer does not cost. The more storage used, the less it will cost.

S3 objects can be encrypted too and HTTPS end point security can also be applied.

Remember Bucket names should be unique across all AWS. U-N-I-Q-U-E !

RRS - Reduced redundancy storage  : has 99.99 % durability vs "eleven nines" for standard storage type. Can be used for the data which can be reproduced easily. Which can be recreated easily.

Lifecycle policies & object versioning - We can have unlimited versions if enabled on S3. We can archive\backup older versions into Amazon Glacier.

Now what is Amazon Glacier - Its an archival storage. Used for data not frequently accessed. Takes several hours to check in and check out. 0.1/gig per month.

Amazon Storage Gateway - This is the connection between local data center to cloud services like Amazon S3. Has two types,

• Gateway-Cached Volumes - It will create a storage volume & mount as iSCSI device on premises. It will then store the data to Amazon S3 but will cache frequently accessed data on premises. To have faster access time.
• Gateway-Stored Volumes - Stores all data locally and backs up the data as incremental backups on S3.

Amazon Import/Export - Users can physically snail mail large amount of data to Amazon. Amazon will upload it to cloud within one day of receiving the data.

Database services

Amazon RDS - Fully managed DB service from Amazon. No access to underlying OS allowed. Patching etc is all managed by AWS.

DBs supported by RDS -

1. MySQL
2. PostgreSQL
3. Oracle
4. MS SQL server
5. Aurora

Aurora - Forked from MySQL by Amazon. Has 5 times better performance than MySQL with lower cost.

Amazon ElastiCache - In-memory cache for high performance DB queries. Caches results of queries etc. Application needs to be built to work with either Redis/Memcached.

Amazon DyanoDB - NoSQL fully managed service. Fully managed by AWS. Built as fault tolerant so in backend it syncs data in all AZs for the region. Easily integrates with Elastic MapReduce.

Amazon RedShift - Used as petabyte scale data warehousing service.

Analytics

Amazon Elastic MapReduce - Spins EC2 instances with Hadoop clusters. We have access to underlying OS.

App Services

Amazon SWF (Simple Work Flow) - used for work flow executions. Control panel to monitor task work flow. Scalable parallel EC2 processing. Service can be used with on-premises servers too. Guarantees execution of work flow.

Amazon SQS (Simple Queue Service) - Similar to Azure queues. Guarantees delivery of at least 1 message but not guarantees no duplicates. 

Amazon SNS (Simple Notification Service) - Co-ordinates delivery of messages to specific end points. Endpoints can be SQS, Email, SMS, HTTPS, Applicatoin etc.

Deployment Services

Amazon EB (Elastic Beanstalk) - Deploy complete app environment automatically. Support for docker containers.

Amazon CloudFormation - Allows us to code infra and deploy resources based off a pre-build template. Good for disaster recovery. We can even version control our AWS infrastructure.

Management Services

IAM - Identity Access Management - Manage permissions to AWS resources. Resource level\API call permissions can be managed.

CloudTrail - Logs all API calls made to AWS.

CloudWatch - Monitor services like EC2. Provides centralized logging for performance metrics etc. Is heavily used in AutoScaling.

Directory services - Can connect on-premise Microsoft Active Directory with AD connector. Also has ability to setup and operate new directory.