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What infrastructure automation means
In many businesses, servers are built by hand over time. Each one accumulates small changes that were never written down, and if it disappeared tomorrow, rebuilding it would mean piecing together old notes and guesswork. Infrastructure automation, often called infrastructure as code, replaces that with files that describe exactly what should exist.
There are two layers. Provisioning creates the resources themselves: servers, networks, firewalls, DNS records, storage buckets. Configuration sets up what runs on them: packages, users, services and settings. Together they let you recreate your environment reliably and see every change in version control.
Who needs it
- Businesses with more than a couple of servers that should be configured the same way.
- SaaS products that need matching staging and production environments.
- Agencies that set up similar infrastructure for each new client project.
- Teams whose disaster recovery plan is currently “we would figure it out”.
- Anyone preparing for a security review that asks how infrastructure changes are controlled.
Even a single server benefits if it is critical to the business. Being able to rebuild it from code turns a potentially long outage into a predictable recovery, and makes moving to a new provider far less daunting.
What’s included
- An inventory of existing infrastructure and how it was created.
- Terraform code for cloud resources: servers, networks, firewalls, DNS and storage.
- Ansible playbooks or equivalent for server configuration.
- Import of existing resources where practical, rather than rebuilding everything.
- Remote state storage with locking, so two people cannot change the same thing at once.
- A review workflow: planned changes shown before they are applied.
- Optional CI integration so infrastructure changes run through a pipeline.
- Documentation and a rebuild runbook.
We write the code so it is organised by purpose, such as networking, servers and DNS, with variables for anything that differs between environments. That keeps it readable and makes adding a new environment largely a matter of new values rather than new code.
How we deliver it
- Inventory what exists, including resources created by hand in provider consoles.
- Agree scope: which resources to codify first, usually the most critical or most frequently changed.
- Write the code and import existing resources, checking the plan shows no unintended changes.
- Codify server configuration and test it by building a fresh server from scratch.
- Set up the review workflow and hand over with documentation.
Importing existing resources is done carefully and in small groups. After each import, the plan must show no changes before we move on, which ensures the code describes what is really running rather than an idealised version of it.
Tools we use
Terraform is our main provisioning tool, with providers for AWS, Google Cloud, Azure, DigitalOcean, Hetzner and Cloudflare. Ansible handles server configuration because it needs no agent on the servers and is readable by non-specialists. cloud-init is useful for first-boot setup. GitHub Actions or GitLab CI can run plans on pull requests so changes are reviewed before they are applied.
We avoid clever abstractions in the code. Plain, explicit definitions are easier for your team to read, review and change safely, and that matters more over the years than saving a few lines.
Manual setup versus infrastructure as code
| Question | Manual setup | Infrastructure as code |
|---|---|---|
| How was this server built? | Depends who you ask | Read the code |
| Who changed the firewall last week? | Hard to tell | Visible in version control history |
| Can staging match production? | Only approximately | Built from the same definitions |
| How long to rebuild after a failure? | Unpredictable | A known, tested procedure |
| Can a new team member understand it? | Only with a long handover | The code is the documentation |
What affects timeline and cost
Codifying a small, well-understood setup is quick. More time is needed for large estates, many resources created by hand in consoles, several cloud providers, or servers with years of undocumented configuration that must be discovered before it can be written down. The tools themselves are free to use in most cases; cloud resources remain billed by your provider.
You do not need to automate everything at once. Starting with the most critical server or the resources that change most often gives useful results quickly, and the rest can follow as time allows.
Common mistakes
- Continuing to make changes by hand in the console, so the code drifts from reality.
- Storing state files on one person’s laptop, or committing them with secrets inside.
- Applying changes without reviewing the plan first.
- Codifying everything in one giant file that nobody wants to touch.
Related: CI/CD Pipeline Setup, Ubuntu Server Setup and Environment Configuration. See all DevOps & Deployment services, the DevOps guide, or contact us.
Frequently asked questions
Can you codify infrastructure that already exists?
Yes. Terraform can import many existing resources, and we check that the plan shows no changes before relying on it.
Terraform or Ansible?
They do different jobs. Terraform creates infrastructure; Ansible configures what runs on servers. Most setups use both.
Does this only work on AWS?
No. Terraform supports DigitalOcean, Hetzner, Google Cloud, Azure, Cloudflare and many others.
What if someone changes something by hand?
The next plan shows the difference, so drift is visible. We recommend restricting console changes once infrastructure is codified.
Will our team be able to maintain it?
Yes. We keep the code straightforward, document it and walk your team through making a change.
Talk to us about infrastructure automation
Servers defined in code, so rebuilding one is a command rather than a memory test.