Migration Flashcards
Regarding database migration, what is SCT and what does it do?
Schema Conversion Tool
Allows you to convert database schemas from one engine to another.
What is DMS on a high level?
A server running replication software
What are the database migration steps when using DMS? (5)
- Create Source and Target connections
- Migrate the database Schema
- Set up the data replication process
- Initiate the full load (and a subsequent CDC) and apply
- Switch your production environment to the new database
Step 5 doesn’t apply to CDC only migrations.
TRUE or FALSE?
DMS cannot migrate between source and target endpoints that have different engines.
FALSE
It can, using the Schema Conversion Tool
TRUE or FALSE?
You can use AWS Schema Conversion Tool to convert databases running on EC2 or data stored in S3
TRUE
What are the 3 different database migration types to know for the exam?
- Full Load
- Full Load and Change Data Capture (CDC)
- CDC only
What is Full Load migration?
All existing data from the source is moved to the target.
What is Full Load and CDC migration?
All existing data from the source is moved to the target.
CDC captures changes to the source tables during migration.
Which AWS services would you use to migrate large data stores?
AWS Snowball with DMS
What problem can occur when migrating large data stores?
Network throttling
What is a CDC only migration?
It does not move any pre-existing data.
Only the changes that occur on the source database after the migration starts are moved.
What are some use cases for a CDC only migration? (3)
- Logging what data has changed
- Replicating data between different environments (e.g. development and testing)
- Real time data integration (i.e. to feed data into other systems in real time, e.g. for analytics)
TRUE or FALSE?
When using DMS, one of the endpoints must be within AWS.
TRUE
What does SMS stand for?
Server Migration Service
Migration Hub is a place to… (3)
- Discover existing servers
- Plan migrations
- Track migration status
It works with other services to actually do the migrations.
What are the migration phases?
- Discover (find servers and dbs to plan your migration)
- Migrate (connect tools to migration hub and begin migrating)
- Track
What does SMS do?
Automates migrating on-prem servers to AWS
How does SMS work?
It replicates server VMs to AWS AMIs. These can then be deployed on EC2 instances.
TRUE or FALSE?
Migration Hub carries out your migration
FALSE
It just plans it, it doesn’t do it for you.
Exam tip: For questions involving tracking and planning migrations, think of…
Migration Hub
What are 3 benefits that SMS provides?
Server Migration Service
- Simplifies migrations
- Migrates different types of VMs, incl. from other cloud providers
- Minimizes downtime
What is the pricing model for DMS?
You only pay for the replication instances and any additional log storage.
Data transfer is free.
When would you NOT use Direct Connect for migration?
- Too much data
- You don’t need the connection to the DC after the migration is done
What are the devices in the Snow Family in order of size?
Snowcone
Snowball Edge
Snow Mobile
How much storage do you get with Snowcone?
8 TB
What are two use cases for Snowcone?
- IoT stuff
- data that’s already been processed
How much storage do you get with Snowball Edge?
approx 50 to 80 TB
What are two use cases for Snowball Edge?
- off-grid computing
- migration
How much storage do you get with Snow Mobile?
100 PB
