Infrastructure as Code for ERP#
If you're deploying ERP infrastructure—whether on-premise, cloud, or hybrid—Infrastructure as Code (IaC) transforms ad-hoc provisioning into repeatable, auditable, and version-controlled deployments.
Terraform has become the industry standard for Infrastructure as Code across multiple cloud providers. For ANZ organisations running ERP systems on AWS, Azure, or Google Cloud, Terraform provides a consistent way to manage infrastructure lifecycle.
---
Why Infrastructure as Code for ERP?#
Repeatability#
ERP implementations often span multiple environments: - Development - Test - Staging - Production - Disaster recovery
Infrastructure as Code ensures each environment is provisioned identically, reducing "works on my machine" problems.
Auditability#
Every infrastructure change is: - Recorded in version control - Reviewed before application - Traceable to who made the change - Documented through code
Disaster Recovery#
When disaster strikes: - Infrastructure can be recreated from code - Recovery is faster and more reliable - Documentation is inherent in the code
Compliance#
For regulated industries: - Infrastructure configuration is documented - Changes require approval through code review - Audit trails are automatic
---
Terraform Fundamentals for ERP#
Provider Configuration#
`hcl
provider "aws" {
region = "ap-southeast-2" # Sydney
}
provider "azurerm" {
features {}
# Australian regions for data residency
}
`
Resource Definition#
`hcl
resource "aws_instance" "erp_app" {
ami = var.erp_ami
instance_type = var.instance_type
subnet_id = aws_subnet.erp_subnet.id
tags = {
Name = "erp-application"
Environment = var.environment
}
}
`
Module Structure#
`
terraform/
├── modules/
│ ├── erp-network/
│ ├── erp-compute/
│ ├── erp-database/
│ └── erp-monitoring/
├── environments/
│ ├── dev/
│ ├── test/
│ └── prod/
└── global/
└── iam/
`
---
ERP-Specific Terraform Patterns#
Network Isolation#
ERP systems typically require isolated networks:
`hcl
module "erp_network" {
source = "./modules/erp-network"
vpc_cidr = var.vpc_cidr
private_subnets = var.private_subnets
public_subnets = var.public_subnets
enable_vpn = true
vpn_cidr = var.office_cidr
}
`
Database Infrastructure#
Managed databases with appropriate configurations:
`hcl
resource "aws_rds_cluster" "erp_database" {
engine = "aurora-postgresql"
engine_version = "15.4"
database_name = "erp"
master_username = var.db_username
master_password = var.db_password
backup_retention_period = 35
skip_final_snapshot = false
deletion_protection = true
}
`
Compute Infrastructure#
Application servers with auto-scaling:
`hcl
resource "aws_autoscaling_group" "erp_app" {
name = "erp-app-asg"
vpc_zone_identifier = module.erp_network.private_subnet_ids
min_size = var.min_instances
max_size = var.max_instances
launch_template {
id = aws_launch_template.erp_app.id
version = "$Latest"
}
}
`
---
State Management#
Remote State#
Store Terraform state remotely for team collaboration:
`hcl
terraform {
backend "s3" {
bucket = "company-terraform-state"
key = "erp/production/terraform.tfstate"
region = "ap-southeast-2"
encrypt = true
dynamodb_table = "terraform-locks"
}
}
`
State Locking#
Prevent concurrent modifications: - Use DynamoDB (AWS) - Use Azure Blob Storage locks (Azure) - Never modify state simultaneously
State Security#
Terraform state contains sensitive data: - Encrypt at rest - Restrict access through IAM - Audit state access - Consider state encryption
---
ANZ-Specific Considerations#
Region Selection#
`hcl
variable "aws_region" {
default = "ap-southeast-2" # Sydney
}
variable "azure_region" {
default = "Australia East" # Sydney
}
`
For multi-region:
`hcl
provider "aws" {
alias = "sydney"
region = "ap-southeast-2"
}
provider "aws" {
alias = "melbourne"
region = "ap-southeast-4"
}
`
Data Residency#
Ensure resources are in compliant regions: - Use region constraints in variables - Add validation for region values - Document data residency in comments
Cost Management#
Tag all resources for cost allocation:
`hcl
locals {
common_tags = {
Project = "ERP"
Environment = var.environment
CostCenter = var.cost_center
Owner = var.owner
ManagedBy = "Terraform"
}
}
`
---
Operational Workflows#
Planning Changes#
`bash
terraform plan -out=tfplan
`
Review plan output before applying.
Applying Changes#
`bash
terraform apply tfplan
`
Apply only reviewed plans.
Drift Detection#
Regularly detect configuration drift:
`bash
terraform plan -detailed-exitcode
`
Emergency Changes#
For urgent manual changes: 1. Document the change 2. Update Terraform code to match 3. Run terraform import if needed 4. Verify next plan shows no changes
---
Module Design Best Practices#
Composable Modules#
Design modules that can be combined: - Network module - Compute module - Database module - Monitoring module
Variable Validation#
`hcl
variable "environment" {
type = string
validation {
condition = contains(["dev", "test", "prod"], var.environment)
error_message = "Environment must be dev, test, or prod."
}
}
`
Output Key Values#
`hcl
output "database_endpoint" {
value = aws_rds_cluster.erp_database.endpoint
sensitive = true
}
output "application_url" {
value = aws_lb.erp_app.dns_name
}
`
---
Monday Morning Action Plan#
- Inventory Current Infrastructure: Document all infrastructure supporting your ERP.
- Choose a Starting Point: Begin with a non-critical component (e.g., monitoring, test environment).
- Set Up State Management: Configure remote state backend before writing significant code.
- Create Module Structure: Design module hierarchy that matches your infrastructure.
- Implement Gradually: Convert existing infrastructure to code incrementally, not all at once.
---
Conclusion: Infrastructure as Code Is a Journey#
Terraform provides powerful infrastructure management capabilities, but adopting Infrastructure as Code is a journey, not a one-time project.
For ANZ organisations, the key is: - Start small with non-critical infrastructure - Build team capability gradually - Establish state management and workflows early - Expand coverage as confidence grows
The investment in Infrastructure as Code pays dividends in reliability, auditability, and disaster recovery capability.