What is EC2

EC2 stands for Amazon Elastic Compute Cloud. It lets you rent virtual servers on AWS so you can run apps databases and batch jobs without buying racks full of blinking hardware. Think of it as leasing server brainpower by the hour or by the month with fewer cables and more invoices.

Key concepts to know

• Instances are the virtual machines you launch. They come with CPU memory storage and networking options tuned for different workloads.
• AMIs are machine images that capture an operating system and configuration so instances start the same way every time.
• EBS is block storage that stays around even if your instance stops. Use gp3 or io2 for fast disks when you care about latency.
• Security groups act as virtual firewalls controlling inbound and outbound traffic. Apply least privilege and stop letting everything talk to everything.
• Pricing models include on demand reserved spot and savings plans so you can balance cost and reliability instead of guessing and crying later.

How to pick instances without gambling

Match the instance family to your workload. CPU bound jobs want compute optimized families. Memory heavy databases want memory optimized families. If you pick a general purpose type because it sounds safe you will pay more for less speed and live with regret.

Reusable environment tips

Create AMIs for reproducible environments and use snapshots to backup EBS volumes. This makes disaster recovery less of a DIY horror story. Attach EBS volumes if you need persistent storage and choose gp3 or io2 for IOPS hungry workloads.

Security and networking

Apply security groups with the principle of least privilege. Only open the ports you need and restrict sources to known IPs or other AWS services. If everything is open your server is a free buffet for bad actors.

Scaling monitoring and cost control

• Scaling options include manual scaling scheduled scaling and auto scaling groups that replace unhealthy instances and add capacity under load.
• Monitoring with CloudWatch helps spot performance bottlenecks and keeps cost surprises to a minimum.
• Cost optimization means using spot instances for fault tolerant batch jobs and reserved or savings plans for steady state workloads.

Operational hygiene

Tag resources consistently with project environment and owner. Good tags make cost allocation and troubleshooting far less painful. Also automate where you can and keep human clicks to a minimum.

In short EC2 gives you flexible virtual servers with many knobs. Use the right instance family automate AMIs and snapshots secure your network and pick the pricing model that does not surprise your manager. Do that and you will sleep better at night even when a minor cloud tantrum happens.