AWS Certified Solutions Architect - Associate Flashcards
(30 cards)
SHARDS
Think Kinesis Streams. It is the only form of Kinesis that uses shards.
Default is storage in shards for 24hrs. Can be configured up to days
Kinesis Firehose
NO PERSISTENT STORAGE (like streams>shards). Data has to be analysed as it comes in.
Can use lambda functions. Data comes in, triggers lambda then outputs to s3 or Redshift (although not directly to Redshift. Needs to go to s3 first then import in to Redshift) or Elasticsearch cluster and Splunk
SQS - FIFO Queue
First-in First-Out Delivery
Exactly Once Processing
Limited to 300 transactions per second
SQS
Is PULL based (not pushed = SNS)
Messages are 256KB in size
Messages can be kept in the queue from 1 minute to 14 days
Default retention is 4 days Important to remember
SQS - Visibility Time Out
The amount of time that a msg is invisible in the Q after a reader picks up that msg.
DEFAULT 30 seconds
MAXIMUM is 12HRS
Provided the job is processed before the visibility timeout expires, the msg will then be deleted from the Q.
If not processed in time. The msg will become visible again and another reader will process it.
This CAN result in the same msg being delivered twice/
SQS Polling
SHORT POLLING - returns immediately even if Q is empty LONG POLLING (Saves Money) - doesn't return a response until a message arrive sin the Q or the long poll times out.
SWF (if TASK is mentioned think SWF)
Workflow executions can last up to 1 year
SWF presents a task-oriented API (whereas SQS offers a msg oriented API)
SWF ensures a task is assigned only once and never duplicated
SWF keeps track of all tasks/events in an app (For SQS you need to implement your own tracking)
SWF
- WORKFLOW STARTERS
- DECIDERS
- ACTIVITY WORKERS
Workflow Starters - an app that can initiate a workflow. Could be an e-commerce website following the placement of an order, or a mobile app searching for bus times
DECIDERS - control the flow of activity tasks in a workflow execution. If something has finished/failed in a workflow, a decider decides what to do next.
ACTIVITY WORKERS - carry out the activity tasks
SNS vs SQS
Both are messaging systems
SNS - Push
SQS - Polls (Pulls)
Cross-origin resource sharing (CORS)
a mechanism that allows restricted resources (e.g. fonts) on a web page to be requested from another domain outside the domain from which the first resource was served.
CORS is enforced by the client.
EXAM Q - If you see something along the lines of “Origin policy cannot be read at the remote resource”
You need to ENABLE CORS on API Gateway
Attaching a network interface to an EC2 instance
You can attach a network interface to an EC2 instance in the following ways:
1. When it's running (hot attach) 2. When it's stopped (warm attach) 3. When the instance is being launched (cold attach).
IAM database authentication
IAM database authentication is only supported in MySQL and PostgreSQL database engines.
AWS X-Ray
usedto trace and analyze user requests as they travel through your Amazon API Gateway APIs to the underlying services.
Glacier Select
is not a storage service.It is primarily used to run queries directly on data stored in Amazon Glacier, retrieving only the data you need out of your archives to use for analytics.
AWS Glue
is a fully managed extract, transform, and load (ETL) service that makes it easy for customers to prepare and load their data for analytics.
AWS OpsWorks
is a configuration management service that provides managed instances of Chef and Puppet. Chef and Puppet are automation platforms that allow you to use code to automate the configurations of your servers. OpsWorks lets you use Chef and Puppet to automate how servers are configured, deployed, and managed across your Amazon EC2 instances or on-premises compute environments.
AWS Trusted Advisor
analyzes your AWS environment and provides best practice recommendations in these five categories:
Cost Optimization,
Performance,
Fault Tolerance,
Security,
andService Limits.
You can use a mnemonic, such as CPFSS, to memorize these five categories.
Gateway endpoint
for Amazon S3 and DynamoDB service, you have to create a gateway endpoint and then use an interface endpoint for other services.
How will I be charged if my Spot instance is interrupted?
If your Spot instance is terminated or stopped by Amazon EC2 in the first instance hour, you will not be charged for that usage. However, if you terminate the instance yourself, you will be charged to the nearest second. If the Spot instance is terminated or stopped by Amazon EC2 in any subsequent hour,you will be charged for your usage to the nearest second. If you are running on Windows and you terminate the instance yourself, you will be charged for an entire hour.
Amazon S3 notification feature
Amazon S3 supports the following destinations where it can publish events:
Amazon Simple Notification Service (Amazon SNS) topic -A web service that coordinates and manages the delivery or sending of messages to subscribing endpoints or clients.
Amazon Simple Queue Service (Amazon SQS) queue -Offers reliable and scalable hosted queues for storing messages as they travel between computer.
AWS Lambda -AWS Lambda is a compute service where you can upload your code and the service can run the code on your behalf using the AWS infrastructure. You package up and upload your custom code to AWS Lambda when you create a Lambda function.
Data pipeline
is primarily used as a cloud-based data workflow service that helps you process and move data between different AWS services and on-premises data sources. It is not suitable for collecting data from distributed sources such as users, IoT devices, or clickstreams.
Amazon Redshift Spectrum
is a feature of Amazon Redshift that enables you to run queries against exabytes of unstructured data in Amazon S3 with no loading or ETL required.
Snowball vs Snowball Edge
Although an AWS Snowball device costs less than AWS Snowball Edge, it cannot store 80 TB of data in one device. Take note that the storage capacity is different from the usable capacity for Snowball and Snowball Edge. Remember that an 80 TB Snowball appliance and 100 TB Snowball Edge appliance only have 72 TB and 83 TB of usable capacity respectively. Hence, it would be costly if you use two Snowball devices compared to using just oneAWS Snowball Edge device.
