EC2 - Instance Storages Flashcards
What is EBS?
Elastic Block Store
What is an EBS Volume?
Network drive that can be attached to instances.
Does EBS Volume persists data after instance termination?
Yes it does.
How many instance can use 1 EBS volume?
One volume can connect only to one instance.
What are the EBS Volume restrictions?
It is bound to Availability Zones.
Can you have latency with EBS Volumes?
Yes, because they are network attached.
What does Provisioned capacity means for an EBS Volume?
It means and EBS Volume has a fixed size in GBs and IOPS once its created. Billed by the porvisioned capacity.
What is Delete on Termination attribute?
Controls the EBS behaviour when an EC2 instance terminates
* By default, the root EBS volume is deleted (attribute enabled)
* By default, any other attached EBS volume is not deleted (attribute disabled)
What is a typical Delete on Termination attribute use case?
Preserve a root volume after termination.
What is EBS Snapshot?
Its a backup of the volume at a point of time.
Whats the usage of Snapshots?
- Can copy snapshots across AZs
- Backuping data
What are the 3 EBS Snapshots features?
- EBS Snapshot Archive
- cheaper “archive tier”, takes 24 to 72 hours to restore
- Recycle Bin for Snapshots
- setup retention rules for snapshot deletion
- Fast Snapshot Restore (FSR)
- force full initialization of a snapshot to have no latency on the first use $$$
How to protect retention rules?
With the rule lock settings: lock, unlock.
What is AMI?
- Amazon Machine Image
- AMI are a customization of an EC2 instance
What are AMI restricitions?
It is bound to a specific region. (Can be copied across regions).
What are the 3 launch type of EC2 instances?
- Public AMI: AWS provided
- Own AMI: you make it, you maintain it
- AWS Marketplace AMI: made by someone else
How to create an AMI?
- Start an instance and do the customizations
- Stop the instance
- Build AMI, this will create an EBS Snapshot
- Launch instances from the AMI
What is EC2 Instance Store?
a high-performance hardware disk
What is the difference in EC2 Instance Store comapred to EBS Volume?
- Better I/O performance
- EC2 Instance Store lose their storage if they’re stopped (ephemeral)
- Good for buffer / cache / scratch data / temporary content
- Risk of data loss if hardware fails
- Backups and Replication are your responsibility
- very high IOPS
What are the main EBS Volume Types?
- gp2/gp3 : General purpose SSD volume that balances price and performance for
a wide variety of workloads - io1 / io2 (SSD): Highest-performance SSD volume for mission-critical low-latency or
high-throughput workloads - st1 (HDD): Low cost HDD volume designed for frequently accessed, throughput- intensive workloads
- sc1 (HDD): Lowest cost HDD volume designed for less frequently accessed workloads
What are the EBS Volume characterizations?
Size | Throughput | IOPS (I/O Ops Per Sec)
What type of EBS Volumes can be used for boot?
gp2, gp2, io1, io2
What are the uses cases of General Purpose SSD Volumes?
- Cost effective storage, low-latency
- System boot volumes, Virtual desktops, Development and test environments
- 1 GiB - 16 TiB
- gp2 iops and size is linked
- gp3 iops and size is not linked
What are the uses cases of Provisioned IOPS (PIOPS) SSD Volumes?
*Critical business applications with sustained IOPS performance
* Or applications that need more than 16,000 IOPS
* Great for databases workloads (sensitive to storage perf and consistency)
* Supports EBS Multi-attach
What are the uses cases of Hard Disk Drives (HDD) Volumes?
- Cannot be a boot volume
- 125 GiB to 16 TiB
- Throughput Optimized HDD (st1)
- Big Data, Data Warehouses, Log Processing
- Cold HDD (sc1):
- For data that is infrequently accessed
- Scenarios where lowest cost is important
What is EBS Multi-Attach?
- Attach the same EBS volume to multiple EC2 instances in the same AZ
- use case:
- Achieve higher application availability in clustered Linux applications (ex: Teradata)
- Applications must manage concurrent write operations
- Up to 16 EC2 Instances at a time
What is EFS?
*Elastic File System
* Managed NFS (network file system) that can be mounted on many EC2
* EFS works with EC2 instances in multi-AZ
* Highly available, scalable, expensive (3x gp2), pay per use
Whats the typical usage of EFS?
content management, web serving, data sharing, Wordpress
Is EFS compatible with Windows AMIs?
No, it is compatible with Linux based AMIs.
How does EFS scales?
- File system scales automatically, pay-per-use, no capacity planning!
What are the EFS Storage Classes?
- Performance Mode (set at EFS creation time)
- General Purpose (default) – latency-sensitive use cases (web server, CMS, etc…)
- Max I/O – higher latency, throughput, highly parallel (big data, media processing)
- Throughput Mode
- Bursting – 1 TB = 50MiB/s + burst of up to 100MiB/s
- Provisioned – set your throughput regardless of storage size, ex: 1 GiB/s for 1 TB storage
- Elastic – automatically scales throughput up or down based on your workloads
- Up to 3GiB/s for reads and 1GiB/s for writes
- Used for unpredictable workloads
What are the EFS Storage Tiers?
- Standard: frequently accessed files
- Infrequent access (EFS-IA): lower price storage, Enable via policy
What are the EFS Storage Tiers availabilities?
- Standard: Multi-AZ, great for prod
- One Zone: One AZ, great for dev, backup enabled by default, compatible with IA (EFS One Zone-IA)
Whats the diff between EBS and EFS?
EBS volume
* one instance (except multi-attach io1/io2)
* are locked at the Availability Zone (AZ) level
* gp2: IO increases if the disk size increases
* io1: can increase IO independently
* To migrate an EBS volume across AZ
* Take a snapshot
* Restore the snapshot to another AZ
* Root EBS Volumes of instances get terminated by default if the EC2 instance gets terminated. (you can disable that)
EFS
* Mounting 100s of instances across AZ
* EFS share website files (WordPress)
* Only for Linux Instances (POSIX)
* EFS has a higher price point than EBS
* Can leverage EFS-IA for cost savings
