complete

Complete Example - PostgreSQL HA Cluster

This example deploys a complete PostgreSQL HA cluster on OCI including:

• A dedicated compartment
• KMS vault and encryption key
• The PostgreSQL HA cluster module (2 PostgreSQL nodes + 1 etcd witness)
• Network Load Balancer for client connections

Prerequisites

• OCI tenancy with appropriate permissions
• An existing VCN and private subnet
• SSH key pair for instance access
• Terraform >= 1.5
• OCI CLI configured (or API key credentials)

Usage

1. Copy the example tfvars file and fill in your values:

cp terraform.tfvars.example terraform.tfvars
# Edit terraform.tfvars with your OCI credentials and resource OCIDs

2. Initialize and deploy:

terraform init
terraform plan
terraform apply

3. After deployment (allow 5-10 minutes for user-data scripts):

# Check cluster status via SSH to any PostgreSQL node
ssh opc@<node1_ip>
sudo -u postgres patronictl -c /etc/patroni.yml list

Inputs

Name	Description	Type	Default
region	OCI region	string	-
tenancy_ocid	OCI Tenancy OCID	string	-
user_ocid	OCI User OCID	string	-
fingerprint	Base64-encoded API key fingerprint	string	-
oci_prv_key	Base64-encoded OCI API private key	string	-
compartment_id	OCI Compartment OCID	string	-
vcn_id	VCN OCID	string	-
subnet_id	Private subnet OCID	string	-
subnet_cidr	Subnet CIDR block	string	10.0.2.0/24
prefix	Resource name prefix	string	demo
environment	Environment name	string	dev
cluster_name	Patroni cluster name	string	POSTGRES-HA
family_shape	OCI compute shape	string	VM.Standard.E4.Flex
postgres_instance_specs	Instance CPU/memory	object	{ocpus=4, memory=32}
ssh_authorized_keys_postgres	Base64-encoded SSH public keys	list(string)	-

Outputs

Name	Description
load_balancer_ip	NLB IP addresses
postgres_instance_ids	PostgreSQL instance OCIDs
postgres_private_ips	PostgreSQL instance private IPs
witness_instance_id	etcd witness instance OCID
witness_private_ip	etcd witness private IP
nsg_id	Network Security Group OCID