Pre-exam Flashcards
What can you use NACL for?
you can monitor IP addresses
NACL, deny or allow rules?
Can both make deny and allow rules. Must also create both inbound and outbound rules (stateless)
what is stateful?
security groups = both inbound and outbound is created (stateful)
where can you not make deny rules?
in security groups = o Cannot make deny rules since everything is denied by default so you can only make allow rules
what is ElastiCache for?
= to store session state data + improve performance through caching
What are the two properties of Redis?
Redis Elasticache = persistent storage, key-value storage
What are the two properties of Memcached?
o Not persistent
o High-performance distributed memory cache service
what are VPC endpoints for?
PrivateLink = ensures traffic does not traverse the internet
what is Gateway endpoint?
VPC endpoint for S3 + DynamoDB
what is Interface endpoint?
VPC endpoint for almost all services (just not s3 and DynamoDB which is for gateway endpoint)
what is s3 for?
object-based storage
how is the consistency for S3?
o Read after write for PUT
o Eventual consistency for deletes and modifications of objects
what is efs for?
file-storage, NFSv4.1 protocol, also works with block, concurrent ec2 instances.
also good for big data and analytics
how is the consistency for efs?
o Reflects the last write always (always read after write)
what is DynamoDB for?
OLTP workloads
no-sql (schema-less)
serverless (no worry of infrastructure)
how is dynamo db indexed?
Indexed by primary key
what can DynamoDB not do?
No join across tables
how is consistency for dynamo db?
o Eventual consistent for writes
- Can enable “strongly consistent reads” to fix this
is dynamo db serverless?
yes, …. Unless using provisioned throughput
how can joins be made with aurora?
joins across multiple tables possible
how is consistency for aurora?
Low-latency write consistency
what is ALB for?
o HTTP/HTTPS (Layer 7)
o Host and path-based routing
what is NLB for?
o TCP, TLS, UDP, TCP_UDP, (Layer 4)
what is CLB for?
o TCP, Layer 4
o Proxy protocols = TCP as back-end always
how is multi-az replication?
synchronous (active-passive)
how is read replica replication?
Read replica = read performance improved, asynchronous
what are A records for?
Ipv4 (google.com to IP address)
what are AAAA records for?
Ipv6
what are Alias records for?
Used with apex (domain apex digitalcloud.training) to connect to ELB
Alias records let you route traffic to selected AWS resources, such as CloudFront distributions and Amazon S3 buckets. They also let you route traffic from one record in a hosted zone to another record.
what is PTR record?
solves an IP address to a fully-qualified domain name (FQDN) as an opposite to what A record does. PTR records are also called Reverse DNS records
what is identity federation?
= IAM supports federation for delegated access to the Console or AWS APIs
what is STS?
(for single-sign-on) web service that enables you to request temporary, limited-privilege credentials for IAM users or for users that you authenticate (such as federated users from an on-premise directory)
what are Temporary security credentials ?
aws access key, secret key and security token. Valued for default 12 hours, min 15m, max 36h
what is SAML 2.0?
what is usually used for federation (authentication) and grants temporary access based on the users AD credentials so you can access IAM without having a user
what is Cognito for?
used to authenticate users to web and mobile apps
what is user pool?
- Directory in Cognito. Users can sign in to web or mobile apps
- Can also use Facebook, amazon, and SAML to log in
what is identity pool?
- User can obtain temporary AWS credentials to access AWS services
what are the limits for EBS General Purpose?
- 1 GiB to 16 TiB, Max 16,000 iops
- 3 IOPS per GB up to 16,000
what are the limits for EBS IOPS optimized?
- 4 Gib to 16 TiB, max 64,000 iops
- Up to 50 IOPS per GB
what are the limits for EBS throughput optimized?
- Volume 500 Gib to 16 TiB, can burst, max 500/mb/s per volume, 500iops
what are EBS magnetic optimized for?
- Cheap for infrequently accessed
- can be a boot volume
what are the limits for EBS cold?
- Volume 500 GiB to 16 TiB, max 250/mb/s per volume, 250 iops
- Cannot be boot volume
- cheapest version we have
what are some serverless applications?
- API Gateway
- Lambda
- S3
- DynamoDB
- SNS
- SQS
- Kinesis
- AWS Glue
- AWS Fargate (in ECS)
what does Lambda track?
Lambda (tracks latency per request + number of requests + error requests)
what is Raid 0 for?
no redundancy but writes data to multiple disks. Increases performance
what is Raid 1 for?
improve redundancy / availability = mirror
what is kinesis streams for?
real-time processing of streaming data
what is kinesis firehose for?
delivers streams to AWS services such as S3, Splunk, Redshift and elasticsearch
what is kinesis analytics for?
processing and analyzing real-time streaming data
what does Elastic Network Adapter (ENA) offer?
high-performance-computing/network,
what does Elastic Fabric Adapter (EFA) offer?
o High-performance-computing (HPC) for machine learning
o OS by-pass functionality
what is Active-passive ?
failover policy. One instance running and one backup (Multi-az)
what is Active-active ?
multiple instances running at the same time
what is important about simple AD?
fully cloud-based… does not connect to on-premise
what is AD Connector for?
directory gateway to redirect requests to your on-premise AD and eliminates the need for direct synchronization = when you want to use an existing AD with AWS