Lambda

Question 1

What is Lambda?

Answer 1

Compute service where you can upload code and create a Lambda function.

Lambda takes care of provisioning and managing the servers that you use to run your code.

Question 2

Uses for Lambda

Answer 2

Runs in response to Events

Compute Service
- Run in respone to HTTP request using API gateway. API call using AWS SDK

Question 3

Languages supported by Lambda (5)

Answer 3

Node.js
Java
GO
Python
C#

Question 4

Pricing of Lambda

Answer 4

of requests

• 1st million are free
• $0.20 per request after that

Duration

• time code runs (rounded to nearest 100ms) and amojunt of memory you allocate for your function
• $0.00001667 for every GB second used

Question 5

Does Lambda support versioning?

Answer 5

Yes

Can publish 1 or more versions

But after publish a version it is immutable ( can only edit $LATEST)

Lambda latest version is in $LATEST

Question 6

How to split traffic between Lambda function

Answer 6

Use alias and 2 different versions

But can’t do this with the latest version

Question 7

What to use to debug Lambda

Answer 7

X-Ray

Question 8

What is the default type of LambdaFunction

Answer 8

RequestResponse - synchronous. keep connection open until the function returns a response or times out. The API response includes the function response and additional data.

Question 9

Describe LambdaFunction triggered by an event.

Answer 9

Asynchronous. Send events that fail multiple times to the function’s dead-letter queue (if it’s configured). THE API response only includes a status code.

Question 10

How to validate parameter values and user or role has permission to invoke lambda function

Answer 10

DryRun

Question 11

What is the concurrency execution limit for Lambda

Answer 11

1000

But must have minimum of 100 left so other lambda functions can be called concurrently with remaining bit.

Can set limit for each function but all functions cannot exceed 1000

Question 12

If want to deploy to dev, test, and prod what feature of lambda should you use if you want different function for each.

Answer 12

Environment variables

Question 13

Lambda feature for Zip archive that contains libraries, dependencies and other custom runtime info.

Answer 13

Layers

Question 14

CloudWatch metrics for Lambda

Answer 14

total invocation requests

latency/Duration

error rates

throttles

Iterator age

Dead Letter Queue errors

Question 15

What does it mean with you recieve InvalidParameterValueException

Answer 15

one of parameters in request is invalid

Question 16

CodeStroageExceededException

Answer 16

exceeded max total code size per account

Question 17

ResourceConflictException

Answer 17

resource you want to create already exists

Question 18

ServiceException

Answer 18

AWS Lambda service has internal error

Question 19

How to make libraries available to Lambda function

Answer 19

Upload deployment package to Lambda

Store deployment package in S3 bucket then upload (required for packages over 50MB)

Create deployment package containing function code and libraries

If need for multiple lambda functions use Layers

Question 20

Max memory allocation for Lambda function

Answer 20

3GB or 3008MB

Question 21

Default memory size Lambda

Answer 21

128MB