This image shows a VCN with an internet gateway and a NAT gateway.

Within the VCN, there are five regional subnets, each of which has a security list and route table. The subnets contain:

• Subnet 1: a primary-failover pair of load balancers.
• Subnet 2: a Bastion host.
• Subnet 3: a Jenkins controller node with an active healthcheck.
• Subnet 4: a Jenkins agent node, in fault domain one.
• Subnet 5: a Jenkins agent node, in fault domain two.

The Jenkins nodes are deployed by the Bastion host.

Requests from the internet flow in through the internet gateway to the load balancers, and are then forwarded to the Jenkins controller node. The controller node then communicates with the agent nodes.

The NAT gateway enables one-way access from all three Jenkins nodes to the internet.