My Tech Blog (EC2)

1. Scalability & High AvailabilityScalability(확장성) means that an application / system can handle greater loads by adapting.There are two kinds of scalability  - Vertical Scalability - Horizontal Scalability (=elasticity) 탄력성, 수평 확장성Scalability is linked but different to High Availability ( 확장성 != 고가용성)2. Vertical Scalability - 수직 확장성Vertically scalability means increasing the size of the instanc..

1. The most likely reason your team member is unable to attach the EBS volume to an EC2 instance `in us-east-1b` is that EBS volumes are tied to a specific Availability Zone (AZ) upon creation. Since the volume was originally attached to an EC2 instance in us-east-1a, it is restricted to that AZ and cannot be directly attached to an instance `in us-east-1b`. us-east-1a에서의 EC2 인스턴스를 종료하여, 이 인스턴스에..

EBS vs EFS1. EBS(Elastic Block Storage)▶EBS volumesOne instance (except multi-attach io1 / io2) - 한 번에 하나의 인스턴스만 연결are locked at the Availability Zone (AZ) levelgp2: IO increases if the disk size increasesgp3 & io 1: can increase IO independently▶To migrate an EBS volume across AZTake a snapshotRestore the snapshot to another AZEBS backups use IO and you shouldn't run them while your application..

1. Amazon EFS(Elastic File System) Managed NFS (network file system) that can be mounted on many EC2EFS works with EC2 instances in multi-AZHighly available, scalable, expensive (3x gp2), pay per use Use cases: content management, web serfing, data sharing, WordpressUses NFSv4.1 protocolUses security group to control access to EFSCompatible with Linux based AMI (not Windows)Encryption at rest us..

1. EBS Volume Types1-1. What is EBS Volume Types▶ EBS Volumes come in 6 typesgp2 / gp3 (SSD): General purpose SSD volume  that balances price and performance for a wide variety of workloads.io 1 / io 2 Block Express (SSD): Highest-performance SSD volume for mission-critical low-latency or high-throughput workloadsst 1 (HDD): Low cost HDD volume designed for frequently accessed, throughput-intens..

1.  What's AMI ?AMI = Amazon Machine Image▶ AMI are a customization of an EC2 instance▶ AMI(Amazon Machine Image)는 AWS에서 EC2 인스턴스를 생성할 때 사용하는 템플릿이다.▶ AMI는 EC2 인스턴스를 쉽게 생성하고 관리할 수 있도록 도와주는 OS + 설정 패키지로 운영 체제(OS), 애플리케이션, 실행 환경 설정 등을 포함한 EC2 인스턴스의 사본(이미지)이다.You have your own software, configuration, operating system, monitoring...Faster boot  / configuration time because all your software is pre-p..

1. EC2 Instasnce Storage Section1-1 .What's an EBS Volume?An EBS (Elastic Block Store) Volume is a network drive you can attach to your instances while they runIt allows your instances to persist data, even after their termination- EBS 볼륨을 사용하면 인스턴스가 종료된 후에도 데이터를 지속할 수 있다. 인스턴스를 재생성하고 이전 EBS볼륨을 마운트하면 데이터를 다시 받을 수 있다. They can only be mounted to one instance at a time (at the CCP level)- But some..

1. You launched an EC2 instance to host a NodeJS application. After installing all the necessary software and configuring the application, you recorded the public IPv4 address of the EC2 instance for access. Then, you stopped the instance and restarted it to complete the application setup. However, after restarting, you were unable to access the EC2 instance and noticed that its public IPv4 addr..