AWS SQS Flashcards
What is SQS?
It is a message Q service.
What is the max size of an SQS message?
256KB
What is short and long polling?
- Short is where you sample a subset of the servers and will receive message form just those servers.
- Long poll is where you wait for the message to arrive. (1 - 20 sec)
I have data larger than the 256KB limit on an SQS Q, how cna I deal with this larger data?
Put it in S3 and reference form message SQS
What is the two different Q types available?
Standard
FIFO
I need 1000 operation per second, what Q types should I use?
Standard Q are unlimited
FIFO are limited to 300 operations per second.
What is the visibility time out?
When you poll, the message becomes invisible and time starts, when the time expires the message will become visible again.
I what to have lambda be invoked with messages are in SQS Q, how can I do this?
This is a feature now available.
What is SQS good for?
- It is good for acting as a buffer for incoming data to a Database
- Decouple applications
I need to retain messages in an SQS Q for 10 days, do I need to make changes form the defaults?
Yes, the default is 4 days, you need to increase this to 10 days.
What is the max retention time for an SQS Q?
14 days
What is the default visibility time out?
30 sec, it cna be up to 12 hrs
What is the max visibility time out?
12hrs
What is a dead letter Q in SQS?
THis is where messages cannot be delivered, they are sent to a second Q.
My organization has a policy of encryption at rest, how can I ensure messages at rest are encrypted?
SQS has the option to encrypt messages at rest
When encrypting SQS messages at rest, what KMS key cna I use?
You select a CMK to use form AWS KMS
I need to store messages that are 2GB in size, I am writing my app and have flexibility, how can I do this?
There is an SDK that enables you to store 2GB messages, it does this by pushing the message to thS3 and then to SQS.
I am creating a loosely coupled architecture, what service can I use to decouple my application?
SQS
What is the difference between standard and FIFO Q?
Standard gives no guarantee of message order
FIFO gives first in first out.
What is Amazon MQ, is it SQS?
No amazon MQ is Apache MQ as a service by amazon.
When should I use SQS over Active MQ?
If the app is new it should be SQS, itf the app is coming from on-prem them it my be compatible with Apache MQ )( Amazon MQ)