EBS Flashcards
What is EBS?
Elastic Block Store - An EBS volume is a network drive you can attach to your instances while they run
Give some restrictions when using EBS
- Can only be mounted to one instance at a time
- Bound to a specific availability zone
- Have to provision the EBS volume capacity (size in GBs, IOPS (input/output per second)
How can you move an EBS volume across AZs?
Snapshot the volume in order for it to be moved across AZs.
What is the Delete on Termination attribute? Give one example when you would not want this enabled
If enabled, the EBS volume is deleted when an attached EC2 instances terminates.
(By default, the root EBS volume is deleted)
Example: Preserve the root volume when an instance is terminated by disabling this attribute.
Why would you move an EBS snapshot to an ‘archive tier’?
Archive is 75% cheaper
What is the EBS recycle bin?
Allows recovery of snapshots in the case of accidental deletion - rules can be set up to retain a deleted snapshot for a specified amount of time, 1 day to 1 year
What is FSR?
Fast Snapshot Restore - force full initialization of snapshot to have no latency on the first use. Expensive
What is an AMI?
Amazon Machine Image: a customization of an EC2 instance
What does creating an AMI allow for?
Allows you to add your own software, configuration, operating system, monitoring etc.
Allows for faster boot/configuration time as software is pre-packaged
What is an EC2 instance store?
A high-performance hardware disk attached to an EC2 instance
What are the advantages of an EC2 instance store over EBS?
Better I/O
What are the disadvantages of an EC2 instance store over EBS?
Instance Store loses its data if it is stopped (ephemeral)
Risk of loss of data if hardware fails
What is a use case for an EC2 Instance Store
Buffer/cache/scratch data/temporary content
What are the general purpose EBS volume types?
gp2/gp3 - general purpose SSD that give cost effect storage with low latency
What is the difference between gp2 and gp3?
With gp3 you can independently set IOPS and throughput, whereas with gp2 they are linked.
What are the Provisioned IOPS EBS volume types?
io1/io2 - provide high, sustained IOPS performance
What is the use case for PIOPS?
Databases workloads (sensitive to storage performance and consistency).
Good for critical business applications with sustained IOPS performance or applications that need > 16,000 IOPS
What are some features of io2 Block Express?
4GiB to 64TiB
>64,000 IOPS or 1,000 MiB/s of throughput
Sub-millisecond latency
Supports EBS multi-attach
Describe HDD EBS volumes
Hard Disk Drive
Cannot be boot volume
What is a use case for HDD EBS volumes
Throughput Optimized HDD st1- Big Data, Data Warehouses, Log Processing
Cold HDD sc1 - Infrequently access data, cost efficiency
What is a use case of gp2/gp3?
Low-latency interactive apps
Dev and test environments
What are the features of EBS multi-attach?
io1/io2 family
Attach the same EBS volume to up to 16 EC2 instances
Each instance has full read & write permissions to the high-performance volume
What is a use case of EBS multi-attach?
Achieve higher application availability in clustered Linux applications (e.g., Teradata)
Applications must manage concurrent write operations
What is EFS?
Elastic File System - a managed network file system (NFS) that can be mounted on many EC2
Give two features of EFS
Works with many EC2 instances in multi AZ
Highly available, scalable, expensive (3x gp2), pay per use
What are some use cases of EFS?
Content management, web serving, data sharing, wordpress.
What AMIs is EFS compatible with?
Linux based (NOT Windows)
Describe the two EFS storage tiers
Storage tier: move file after N days
Standard: for frequently accessed files
Infrequent access (EFS IA): cost to retrieve but lower price to store.
What are the differences between standard/regional and one-zone availability and durability for EFS?
Standard: Multi AZ, great for prod
One Zone: Single AZ, great for dev, backup enabled by default, compatible with IA
Can you use an AMI in one region to create an EC2 instance in another?
Not directly - the AMI can be copied across to the target region first, as AMIs are specific to a region.
What is the peak EBS IOPS or equivalent GB?
16,000 IOPS or 5334 GB volume
What is the max IOPS of io1/io2/io2 block express volume types?
64,000 for io1/io2 on Nitro instances, 32,000 on other; 256,000 for io2 block express
What is the max IOPS of gp2/gp3 volume types?
16,000
What is the max IOPS of st1/sc1 volume types?
500 and 250 respectively
