Terraform OpenStack Infrastructure

This project configures and deploys an OpenStack infrastructure using Terraform. The setup includes a bastion host and private instances, with SSH access and network security tailored for secure management and controlled access.

Project Structure

• Key Pair for SSH Access: Generates SSH keys for secure access to instances.
• Cloud-Init Configuration: Configures instance startup scripts for additional setup.
• Security Groups: Sets up firewall rules to manage access to the bastion host and private instances.
• Network Configuration: Configures the network and subnet for the bastion and private instances.
• Compute Instances: Provisions both the bastion host and private instances in OpenStack.

Requirements

• Terraform 0.12+
• Access to an OpenStack environment with API credentials
• SSH access for managing resources via the bastion host

Variables

The following are essential variables required in the terraform.tfvars file:

Variable	Description
private_instance_keypair_name	Key pair name for private instance access
bastion_keypair_name	Key pair name for the bastion host
public_key	Public key path for the SSH key
private_key_path	Path to store the private key
ssh_user	SSH user for connecting to instances
bastion_sg_name	Security group name for the bastion host
bastion_sg_description	Security group description for the bastion host
bastion_ingress_rules	Ingress rules for the bastion host
default_egress_rules	Default egress rules for all instances
private_instance_ingress_rules	Ingress rules for private instances
private_instances_sg_name	Security group name for private instances
private_instances_sg_description	Security group description for private instances
network_name	Name of the network
subnet_name	Name of the subnet
external_network_name	Name of the external network
bastion_instance_name	Name of the bastion host instance
image_name	Image to use for instances
bastion_flavor_name	Flavor for the bastion host
private_instance_name	Name of the private instance
private_instances_flavor_name	Flavor for private instances

Modules

Key Pair Module

• Generates a 4096-bit RSA SSH key pair.
• Uses the generated public key to create an OpenStack key pair for secure instance access.

Security Group Module

• Configures firewall rules for both the bastion host and private instances.
• Allows access to private instances from the bastion host.

Network Module

• Sets up the network and subnet configuration for the bastion host and private instances.

Compute Module

• Provisions compute resources, including a bastion host with a floating IP and private instances accessible only from the bastion host.

Deployment Steps

1. Initialize Terraform:

   terraform init

2. Review the Plan:

   terraform plan

3. Apply Configuration:

   terraform apply

4. Access the Bastion Host:
   Use the private key generated in the private_key_path to SSH into the bastion host.

Notes

• Bastion Host: Acts as the gateway for managing private instances.
• Cloud-Init: Sets up essential configurations on instance launch, including the SSH key and user setup.
• Private Instances: No public IPs are assigned; access is only allowed via the bastion host for added security.

Clean Up

To destroy all resources created by this configuration:

terraform destroy

Troubleshooting

• SSH Issues: Ensure the private key path is correct and permissions are set appropriately.
• Instance Not Accessible: Check security group rules and verify network connectivity.