Storage - EBS Flashcards
What is EBS?
Is used for block level storage with EC2 instances
Why would I use EBS?
Well suited for primary storage of file systems, databases or for any applications that require fine granular updates and access to raw, unformatted, block level storage
What the max performance IOPs by volume type from fastest to slowest?
io2 Block Express = 256k
io2 & io1 = 64k
gp2 & gp3 = 16k
st1 (throughput HDD) = 500
sc1 (cold HDD) = 250
What are the six (seven) different types of EBS volumes?
io2 Block Express (in preview) (SSD)
io2 (SSD)
io1 (SSD)
gp3 (SSD)
gp2 (SSD)
st1 (HDD)
sc1 (HDD)
What is the max throughput by volume from greatest to least?
io2 Block Express = 4k MB/s
io2 & io1 = 1k MB/s
gp3 = 1k MB/s
gp2 = 250 k MB/s
st1 (throughput HDD) = 500 MB/s
sc1 (cold HDD) = 250 MB/s
4,750 - 7500 MB/s per instance
List durability from greatest to least by volume type?
io2 Block Express & io2 = 99.999%
io1 , gp3, gp2, st1, sc1 = 99.8 - 99.9%
What are the use cases for io2?
High performance SSD for business critical lantency sensitive applications
What are the use cases for io1?
high performance SSD volume for latency-sensitive transactional workloads
What are the use cases for gp3?
balances price and performance usually slated for virtual desktops, medium sized databases, low-latency interactive apps, dev & test , boot volumes
What are the use cases for gp2?
general purpose SSD for a wide variety of transactional load for use in boot volumes, low latency interactive apps, dev & test
What are the use cases for st1?
low cost HDD for frequently accessed, throughput-sensitive workloads used for big data, data warehouses, and log processing
What are the use cases for sc1?
lowest storage cost, througput oriented, infrequently accessed data for cold data storage.
List volume size by volume type?
io2 & io1 = 4GB - 16TB
gp3 & gp2 = 1GB - 16TB
st1 & sc1 = 1GB - 16TB
What happens when my instance is terminated?
EBS volume can persist independently of the life of the instance. This can be set by selecting “no” for delete on termination.
What is a snapshot?
a back up of EBS data at a point-in-time. Snapshots protect against the unlikely even of a volume failure.
When can snapshots be conducted?
can be done in real time while the volume is attached, but only capture volume that has successfully been written to the volume, so in this cast detaching is recommended for a clean snapshot
Why are snapshot know as incremental backups?
on the blocks on the device that have changed after your most recent snapshot are saved. This saves on storage cost and decreases the time to create a snapshot
What are some limitations to snapshots?
are regional; can’t delete snapshot if it is the root device, it must first be deregistered; only 5 concurent snapshots are allowed per region; tags are not copied
How is EBS encrypted?
offer data at rest, in transit between EC2 and EBS and snapshot encryption from a volume and from volumes created by a snapshot
How can KMS be used to encrypt volumes?
master keys can be used when encrypted volumes and any snapshots created from your encrypted volumes
How are volumes dealt with when restored by encrypted snapshots?
automaticall encrypted
Can unencrypted volumes be encrypted? Can encryption be removed?
there is no direct way to encrypt a once unencrypted volume or remove encryption. But data can be migrated between unencrypted and encrypted volumes
What is the EBS pricing model?
charged by the amount you provision in GB per month; detached volumes still incur a charge if the storage amount exceeds the free tier; only deletion of a volume can stop charges
Why EBS over S3 and or EFS?
persistent block level storage; high performance for low-lantency workloads; higher than s3 file size max; higher than S3/EFS availability
How is replication achieved with EBS?
via snapshots
durability
stored redundantly in a single AZ
Why wouldn’t you use EBS?
EBS cost more than S3 and is meant for EC2 instances only
Does EBS allow for multi-attach?
Yes, but only for io1. Up to 16 Nitro instances can be attached in same AZ. Only available in us-east-1, us-west-2, eu-west-1, and ap-northeast-2 regions. Volume cannot be modified, enable ordisabled after creation
