Monday, 13 February 2017

AWS Exams - Things to Remember

The primary audience for this post is myself.

I'm taking a number of AWS Certification exams and there are particular areas that I struggle to recall. Here is a list of them SO FAR. This should in no means be considered a complete list.

  • Know which services have native encryption at rest within the region, and which do not. For example, Storage Gateway and Glacier do, but DynamoDB, CF, and SQS do not. 
  • Have a good understanding of how Route53 supports all of the different DNS record types, and when you would use certain ones over others.
  • Know the difference between Directory Service's AD Connector and Simple AD. "Use Simple AD if you need an inexpensive Active Directory–compatible service with the common directory features. AD Connector lets you simply connect your existing on-premises Active Directory to AWS."
  • Elastic IPs are free if you have only one EIP per instance and the associated instance is running.
  • Know what four high level categories of information Trusted Advisor supplies: Cost Optimization, Performance, Security, and Fault Tolerance
  • Know about disaster recovery and the difference between RTO and RPO. 
  • Any CIDR block has 5 reserved IP addresses for AWS. (The first 4 and the last 1)
  • Don’t touch Main route table Create another routetable for route out to internet ( IGW). Last thing you associate this new route table to one of the subnet which will make it public. 
  • Read data storage whitepaper
  • Raid 0(no redundancy / fault tolerance, high speed - low cost) - high I/O performance, Raid 1 - mirror two volumes together (disaster recovery, redundant , no performance improvement, writes latency increase) , Raid 5(R/W operation will continue, more popular, combination of performance, fault tolerance)