CO3404 Distributed Systems
CO3404 Lecture 12 - Subnets & Baston Hosts

Lecture Documents¶

[[CO3404 Lecture 13.pdf]]

Learning Objectives¶

skipped

Basic Infrastructure¶

Creating a VM / EC2 from the portal seems simple but has a lot of background processes and various defaults are used while ok for experimenting but not in real design:
- A VM type and size needs to be specified
- A VM OS image needs to be specified
- Need a system disk for the VM image
- Need a network within which our VM can communicate
GET REST

Deleting Resources¶

If you choose to delete all resources say to save cost then you can recreate them again.
- Azure delete the resource group simply deletes all resources
- AWS need to remember all resources and manually delete each one
- To recreate may need to go through all console steps again.

Organisations need to automate the creation and destruction of their architecture and code deployment.

Cloud providers enable various ways oc creating managing and destroying resources programmatically:
- Software Development Kit (SDK) to call functions
- CLI - Install command line interface which calls functions
- Use a shell / batch script to execute command line commands imperatively
- Use the cloud provider's built-in shell e.g. cloud shell to issue command line commands
- Azure Resource Manager (ARM) templates for delcarative IaC
- e.g. in resource manager | Export template creates a reusable template of your infrastructure.
- AWS CloudFormation templates for delcarative IaC
- Use third party software such as Terraform which is cloud provider agnostic declarative approach

Videos have been posted on videos demonstrating CLI and template approach. To stick to industry standard TerraForm should be used.

demos/terraform/Azure/minimal_vm/main.tf - Minimal to start a VM with TerraForm.

[[CO3404 Lecture 14 - ]]