TD Exam 3 - Long review Flashcards
What are the 2 modes for ECS
EC2 and Fargate
What is a container definition used in ECS
Tells where the image is, and which ports are exposed
What is a task defintion
Represents the app as a whole, can have multiple containers. Has everything except what is in container definition
Where is Task role defined for ECS
In Task definition
What is a service definition in ECS
Defines a service
What is a service in ECS
Defines how Tasks scale, how to distribute load, etc
What is in a Container definition in ECS
Image and ports
What is in a Task definition in ECS
Security (Task role), Container(s) and resources
What is a Task role in ECS
IAM Role which the task assumes
What is in a service in ECS
How many copies, HA, restarts
What is DMS
A managed Database Migration Service
What does DMS use
A replication instance
Can the destination of DMS be onprem?
Yes, either the destination or source needs to be in AWS
What do you define on a replication instance in DMS
Replication task
What are the different states of EC2 instance
Pending
Running
Rebooting
Shutting down
Terminated
Stopping
Stopped
To what state can an instance transtion from pending
Running
To what states can an instance transition from running
Rebooting
Shutting down
stopping
To what state can an instance transition to from Shutting down
Terminated
To what state can an instance transition from terminated
None; It is terminated
To what state can an instance transition from stopping
Stopped
To what states can an instance transition from stopped
Pending
Terminated
What is the pending state
The instance is preparing to enter a running state
When will you be billed when an instance is stopping
If it is preparing to hibernate
What are the 2 types of backup functionality in RDS
Automated Backups
Snapshots
Where are backups from RDS stored
AWS-Managed S3 buckets
Where are RDS backups taken from
Standby instance if you are in multi-AZ mode
Otherwise from primary, so might have performance issues
Are RDS snapshots automatic
No
What are RDS snapshots and backups taken of
An instance, so all the databases within it
Do RDS snapshots expire
No, you have to clean them up yourself, manual or external process to delete
What is a difference between RDS snapshots and backups
Backups are automated
Also backups have transaction logs written every 5 minutes
What is the possible range of values for RDS backups retention
0 to 35 days
Can you keep RDS backups after deleting a db
Yes, but they still expire
Can RDS snapshots and transaction logs be replicated to another region
Yes, but has to be explicitly configured; it is not the default
What happens when you restore an RDS snapshot
A new RDS instance is created; with a new address
Is restoring a backup in RDS fast
No, it restores the backup then replays the transactions from transaction log
What is AWS backup
A fully-managed data-protection service
What is an advantage of AWS backup
IT allows you to consolidate management in one place, across accounts and regions
What are some things supported by AWS Backup
Compute
Block storage
File storage
DBs
Object storage
What is a central component of AWS backup
Backup plans
What can you configure with lifecycles in AWS Backups
When a backup transitions into cold storage and when it expires
What is a vault in AWS Backup
Backup destination - assign KMS key for encryption
What is specified in an AWS Backup backup plan
Frequency
Window
Lifecycle
Vault
Region copy
What is vault lock in AWS backup
Write-once, read-many (lock); you get 72h to delete, then you can’t
Can still have lifecycle to make it expire
Can you do on-demand backup in AWS backup
Yes
Can you do Point-In-Time-Recovery for AWS backup
Yes, for supported product
What is S3 select
Ways to retrieve part of an object instead of the whole object
What is a disadvantage of filtering a large object on the client side
Still use the whole object size of data transfer
What does S3 select and Glacier Select do
Allows you to use SQL-like segments to select part of the object
What is an advantage of S3 select
S3 pre-filters an object, only sends the result
What are some file formats supported by S3 select
CSV, json, parquet, BZIP2 compression for csv and json
What do S3 access points do
Simplify managing access to S3 buckets and objects
What do S3 access points allow you to do
Rather than one bucket with one bucket policy, you create many access points with different policies
Each access point has its own endpoint address
an have different network access control
What is a way of making S3 bucket accessible via VPC
Access point with VPC origin
What types of records are supported with failover routing
primary and secondary
What is the use case for failover routing
Active-passive failover
What is a VPC router
HA, runs in all AZs the VPC is in, each vpc has a vpc router
What is the address of the VPC router
network + 1of the subnet
What does a VPC router do by default
Route traffic between subnets
What is the main route table of a vpc
The route table used by default by a subnet
What happens if many routes match traffic
Higher prefix takes priority
What are possible targets for a route table
Gateway or route table
Can you update local routes in route tables
No
What kind of resilience does an internet gateway have
Region resilient
Can you attach an internet gateway to more than one vpc
no
Can you attach a vpc to more than one internet gateway
no
What are the actions you need to take to make a subnet public
Create IGW
Attah IGW to VPC
Create custom route table
Associate route table
Make the default route the internet gateway
Configure subnet to allocate IPv4 addresses
What happens when you allocate a public IP in a subnet
A record is created in the IGW to associate the instance private ip to the public ip