Chances are I’ve mentioned my certification quite a lot since passing in August, unashamedly, on my third attempt. Over the past few years I’ve sat exams on a range of subjects from machine learning to medieval sonnets and I can without hesitation say that the SAA was the most difficult exam I have taken. Not to mention that a pass mark of 72% for a millennial is generally unheard of – I’m used to a pass mark of 40% with a guaranteed 30% just for turning up. There’s certainly no easy way round it but I just want to outline my five tips for passing this certification and throw in a few key facts along the way…
- Study the content for the Cloud Practitioner exam:
Even if you don’t take the exam, it’s worth starting with the basics. Writing this now, it seems obvious but I ignored this stage and went straight in for the Solutions Architect exam, thinking I had enough time to study and aim for a higher level straight away. I want to emphasise for anyone starting out with their cloud computing journey that knowing the 5 Pillars of the Well-Architected Framework inside out is essential and is the basis for any successful application you will ever deploy in the AWS console. For every question recall the best practices for designing and managing reliable, secure, efficient, and cost-effective workloads with performance efficiency. (Remember: Read replicas are for performance whereas Multi-Availability Zone deployment is for disaster recovery!)
- Be able to draw a diagram of a VPC from memory, even better, deploy one in the AWS console from memory:
I can’t emphasise this enough, at least a third of the questions in the exam every time were focused on the structure of a VPC. Make sure you know how to create public and private subnets, update route tables, and know the differences between security groups and Network Access Control Lists (NACLS). A VPC automatically comes with a default NACL allowing all inbound and outbound traffic. Remember: Security groups are stateful, NACLs are stateless. You cannot block IP addresses on a specific port with security groups but you can with NACLS.
- Do not confuse CloudFront with Elasticache:
Often these are both given as options to a question. They are easy to confuse as both increase application performance. In summary, CloudFront is for content delivery over HTTP. It is placed in front of dynamic content like web applications and, notably, only caches page output. CloudFront is important for scaling a website particularly with geo-location workloads but it does not account for application caching – this is where Elasticache comes in. Elasticache is for in-memory caching and improves application performance latency and throughput for compute intensive workloads. To complicate matters further, Elasticache is available in two different forms: Memcached and Redis. Revise and understand the use cases for each as they will often both be given as options. In the simplest terms, memcached is the simplest model whereas Redis is preferable for complex data types including strings and hashes.
- Be clear on S3 vs EBS vs EFS:
These three are often all given as options so understanding the use cases for each is essential. In short, S3 is for object storage, EBS for block storage and EFS for file storage. S3 is cheaper than EBS and EFS in basic storage costs. However, EBS and EFS have higher performance than S3.
- Know the use cases for the different data migration services:
I was undecided as to whether my final tip should be on databases or data migration and seeing as this was a topic I perhaps did not spend as much time on first time around, I’m going to finish by advising that you understand in depth the use cases for these services:
DataSync: ideal for online transfer.
Snowball: suitable for offline transfer preferable for customers with a bandwidth constraint.
Storage Gateway: for retaining access to migrated data and for ongoing updates from on-premise applications.
Transfer Acceleration: For applications already integrated with Amazon S3 API when high throughput is required.
And there we have it – my five tips for success. Good luck to anyone studying for the SAA exam, hope my advice was helpful! Do not give up, you will get there eventually!
Ellie Woods 