Old Cards Flashcards
How many copies of Aurora for High AVailability
2 per AZ, 3 AZ minimum
How many copies for Aurora’s databases can be lost before affecting: a) Write b) Read
a) 2
b) 3
How does Aurora know there’s a failure
Continuous scans for data block errors
In Route53, what happens to a node with a failed health check
The node is removed until it becomes heathy
What is the retention window for Kinesis Streams
1 - 7 days; the default is 1
Which can run in multi-AZ: Memcached or Redis
Redis
In Cognito, what are Identity Pools
A store of Identity data, providing temporary AWS credentials
Describe the Backup and Restore strategy of RDS
Full backup, with Transaction logs during the day, stored in S3
Restore specified day, along with Transaction logs
What happens to RDS during backups
I/O may be suspended or there may be latency
In DNS, what is a PTR record
It is a reverse A record (ie: an IP address to a domain)
What are 3 levels of Flow Logs
VPC
Subnet
Network Interface
What are 4 types of S3 Encryption
SSE-S3
SSE-KMS
SSE-C
Client Library
What are 3 ways to add scale to a MySQL RDS instance
Add Read Replicas
Provision a larger EC2 instance
Use Elasticache for frequently read, static data
What are 2 types of CloudWatch Dashboards
Global
Regional
What are 3 types of Placement Groups
Clustered: Instances in a single AZ
Spread: Instances in multiple AZs
Partitioned: Instances spread across multiple partitions in each AZ
Which scales Horizontally: Memcached or Redis
Memcached
In Cognito, what are User Portals
User Directories, allowing users to Sign Up and Log into apps using a JSON Web Token (JWT)
Do Elastic Load Balancers have an IP Address
No, they have a DNS Name
What Statuses do Instances have in an Elastic Load Balancer
In Service
Out of Service
What are the Task/Message differences in SWF and SQS
SWF is Task-based
SQS is Message-based
What are the Assigned/Process differences in SWF and SQS
SWF Tasks are assigned only once and never duplicated
SQS Messages may be processed multiple times
What are the Tracking differences in SWF and SQS
SWF tracks Tasks and Events
SQS doesn’t track anything
Given the choice, should I use a CNAME or an Alias record
Always use an Alias; they are cheaper and can be used on an Elastic Load Balancer