EBS - Elastic Block Storage Flashcards
What is an EBS?
An EBS (Elastic Block Store) Volume is a network drive you can attach to your instances while they run. It allows your instances to persist data
Are EBS volumes reusable?
Yes, you can detach it and attach it to another instance
How does an EBS communicate to the instance?
using the network, which means there might be a bit of latency
Are EBS multi AZ?
no
How can I move an EBS volume across AZs?
creating a snapshot of it
What are the EBS provisioned capacity elements?
size in GBs and IOPS
How you get billed for an EBS?
for the provisioned capacity
Can you increase an EBS capacity?
yes, over time
What are the EBS Volume Types?
- GP2
- IO1
- ST1
- SC1
Which are SSD EBS Volume types?
GP2 and IO1
What is the definition for EBS GP2?
General Purpose SSD: volume that balances price and performance for a wide variety of workloads
What is the definition for EBS IO1?
Provisioned IOPS: Highest-performance SSD volume for mission-critical low-latency or high-throughput workloads
What is the definition for EBS ST1?
Throughput Optimized: Low cost HDD volume designed for frequently accessed, throughput-intensive workloads
What is the definition for EBS SC1?
Cold HDD, Infrequently accessed data: Lowest cost HDD volume designed for less frequently accessed workloads
What EBS volumes can be used as boot volumes?
GP2 and IO1
When you shoud not run EBS Snapshots?
while your application is handling a lot of traffic because they use IO
Where are EBS snapshots stored?
In S3, but you won’t’ directly see them
It is necessary to detach EBS volume to create snapshot?
No, but recommended
What is backed up on EBS Snapshots?
only changed blocks, it is incremental
What can you use to automate EBS snapshots?
Amazon Data Lifecycle Manager
What to expect when you create an encrypted EBS volume?
Everything will be encrypted:
- all data
- snapshots and volumes created from snapshots
What leverages EBS encryption?
keys from KMS (AES-256)
How to encrypt an EBS volume?
1-create snapshot
2-encrypt the snapshot
3-create volume
4-attach it to the instance
What is an Instance Store?
a temporary ephemeral storage type located on disks that are physically attached to a host machine
What is the best pros of Instance Stores?
Better I/O performance with very high IOPS
What is the worst cons of Instance Stores?
On stop or termination the instance store is lost
How much can you increase the size of an Instance Store?
Cannot be increased
What is useful for mounting EBS volumes in parallel in RAID settings?
To increase IOPS or to mirror your EBS volume
What are recommended RAID options for EBS?
RAID 0 and RAID 1
What is used for RAID 0?
To increase performance by combining 2 or more volumes and getting the total
disk space and I/O
What is used for RAID 1?
To increase fault tolerance by mirroring a volume to another (2x network)
How behaves EBS GP2 size compared to IOPS?
they are proportional, 3 IOPS per GB, means at 5,334GB we are at the max IOPS
How behaves EBS IO1 size compared to IOPS?
they are independent, you can increase IOPS independently
What happens to EBS volumes when the instance is terminated?
gets terminated as well but you can disable that
What EBS types are better for small / random I/O operations?
SSD
What EBS types are better for large / sequential I/O operations?
HDD
What EBS types are better for large database workloads?
SSD
What is the common max size of EBS volumes?
16 TiB
What are the min size of EBS volumes?
GP2: 1 GB
IO1: 4 GB
ST1: 500 GB
SC1: 500 GB
What is max IOPS for EBS GP2?
16000
What is max IOPS for EBS IO1?
MAX 64,000 (Nitro instances) else MAX 32,000 (other instances)
What is the maximum ratio of provisioned IOPS to requested volume size (in GiB) in EBS IO1?
50:1
What is max IOPS and throughput for EBS ST1?
500 IOPS and 500 MB/s, can burst
What is max IOPS and throughput for EBS SC1?
250 IOPS and 250 MB/s, can burst
What happens when you stop an instance store backed instance?
you can’t stop, just terminate instance store backed instances
