Udemy Flashcards
CloudDeploy can only deploy to:
EC2 instances and Lambda
To deploy an API, you create an API deployment and associate it with a ___. This is a snapshot of the API and is made available for the client to call.
stage
Kinesis stores data in ____-
shards
Commands to push docker to ECR?
- $(aws ecr get-login –no-include-email)
2. docker push [123213.dkr.ecr.eu….]
API gateway URL scheme
https://.execute-api..amazonaws.com/dev/resource
Kinesis streams scales ____ whereas firehose scales ____
- manually
2. automatically
You have an application that requires reading 10 items of 6.6KB per second using eventual consistency. What value should you set for the read throughput?
10
6.6 KB gets rounded to 8 KB, one RCU for eventually consistent is two reads per second of 4 KB, so we have (10 * (8/2))/2 = 10
Your application processes message from an SQS queue. You will write the algorithm that requests more time when the visibility timeout is not enough. Which API should you call ?
ChangeMessageVisibility
In SQS, what is the default visibility timeout for a message?
30 seconds
ALBs support what protocols?
Websockets and HTTP/2
A message published to an SNS topic is distributed to a number of SQS queues in parallel. What is this design pattern called?
Fan out
Identity pools are the containers that Cognito Identity uses to keep your apps’ federated identities organized.
True
To have AWS S3 encrypt an object after it is uploaded, you need to add a header to the HTTP request called
x-amz-server-side-encryption
max size of SQS message?
256KB
In SQS, what does long polling mean ?
Worker will wait to receive a message until a message is available or until timeout
Step functions are specified in _____
JSON
Your organization becomes a huge enterprise. You deployed a customer care website to gather feedback from your customers. You expect that you will receive 180 feedbacks each minute and each feedback will be a text of 9KB in size. All the feedback will be persisted in a DynamoDB table. What should be the required provisioned write throughput ?
27
180 per minute = 3 per seconds, 1 WCU = 1 KB, so 3 * 9 = 27 WCU
Your BI application reads 1200 items from the game table every minute using strong consistency. Each item is 6KB in size. Calculate the required provisioned read throughput for the game table
40
1200 per minute = 20 per second, 6kb round up to 8
20 * (8/4) = 40
Using which AWS API can you return one or more items from one or more DynamoDB tables?
BatchGetItem
Step Functions Standard vs Express
Standard : duration of 1 year (longer workflows, longer duration)
Express: duration of 5 minute (cheaper smaller duration)
Basic idea of AWS Appsync
It is AWS managed GraphQL, and it also can serves as real time data retrieval service using web sockets or MQTT
Could be used for mobile data offline syncing
T/F: ALB, API Gateway, AppSync allow Websockets
TRUE
Your API is getting hit with the same GET request over and over. Your lambda function is overloaded and your bill starts to substantially increase. The GET response returns the same payload and changes only daily. What should you do?
Enable stage cache
EC2 charge granularity
charged by the second
Do load balancers scale instantaneously?
No, contact AWS for a ‘warm up’
RDS transaction logs backed up every 1. ____ and are retained for 2. _____
- five minutes
2. seven days
To update an ASG, you must provide a new ____
launch configuration / launch template
OpsWorks is basically just
Chef and Puppet (VM configuration)
You are making API calls to a third-party API from your backend instances in a private subnet. You were asked to provide a list of IP addresses to whitelist. Which IP address do you provide?
The public IP addresses of any NAT instances in your Amazon VPC
Does S3 have folders?
No, in the test don’t be tricked into folder semantics
For cross region replication of s3 buckets, what is necessary?
Both source and destination buckets must be versioned
T/F: DynamoDB has encryption at rest as default
TRUE
AWS Key Management Service (AWS KMS) is a managed encryption service. Who manages the customer keys in AWS KMS?
customer
If you are using AWS CodeDeploy to deploy a set of 10 AWS Lambda functions and would like to ensure that two functions are updated every 3 minutes, which deployment configuration would be most suitable?
linear
A tag group is applied to each
tag
How to get around default size limit of CF?
Upload template to S3 and refer to its location
Which intrinsic function is used to get the value of a parameter in an AWS CloudFormation template?
Ref
How would you track which resources an AWS CloudFormation stack updated/modified by using AWS CloudTrail?
Search CloudTrail for events where the ClientRequestToken corresponds to the token for this stack action.
Which tool can automatically assign Amazon Route 53 DNS entries for tasks launched by a service?
Amazon Elastic Container Service (Amazon ECS) Service Discovery
You would like to configure Amazon Elastic Container Service (Amazon ECS) Auto Scaling so that when incoming network traffic for a cluster exceeds 20 Mbps, an additional task is launched and again when traffic exceeds 40 Mbps. Which policy type is recommended?
Step Scaling policies
When do control plane and data plane use the same communication protocols?
When using a managed service.
BTW control plane calls APIs
Your company is building a system to send out monthly account status emails to customers using Simple Queue Service (Amazon SQS) with the Standard Queue. How can you prevent a customer from receiving the same email multiple times?
Use the Amazon SQS Standard Queue to track each email that is sent out with Amazon DynamoDB to dedupe the messages.
Also, use SQS FIFO
What does it mean when a message appears in the Amazon Simple Queue Service (Amazon SQS) dead-letter queue?
The message was received by several consumers but never deleted.
A message appears in the dead-letter queue if it is received more than the MaxReceiveCount number of times and never deleted. This indicates that the message causes the consumers to fail.
You use AWS Step Functions to launch front-end servers. Each server launch can take up to 10 minutes. What is the best way to manage this in Step Functions?
Use a Task step with an Activity task.
Not WAIT b/c wait pauses state machine.
Kinesis stream WRITE shard throughput
1 MB / second
Kinesis stream READ shard throughput
2 MB / second
default visibility timeout for SQS
30 seconds
How to prevent unnecessary cpu cycles when polling SQS? In other words, how to reduce the number of empty responses?
adjust ReceiveMessageWaitTimeSeconds
What is the minimum amount of memory that you can allocate to an AWS Lambda function?
128 MB
Max size of Lambda package?
50 MB
Max size of code and dependencies of Lambda beofre compression?
250 MB
Max limit of concurrent Lambda functions?
1000, but this is soft limit that can be changed by contacting AWS
Can AWS X-Ray be used to track all requests to a system?
No. X-Ray tracks only a statistically meaningful number of requests to a system.
ppropriate cost management tool that provides you with real-time guidance for provisioning your resources according to AWS best practices?
Trusted Advisor
Before you terminate beanstalk resources, terminate ___ for cost savings
the environment
Before you terminate you ec2 instances, terminate ___ for cost savings
the load balancer
Before you terminate instance , terminate ____ for max cost savings
EBS volums
Rmember to use SQL syntax in S3 Select!
OK
