add-port

name	add-port
description	Open or close a TCP/UDP port on the instance — updates security list and iptables
allowed-tools	Read, Edit, Bash, Grep, Glob
argument-hint	<port>[/udp] or remove <port>

Add or Remove a Port

Open or close an inbound port across both layers: VCN security list and instance iptables (cloud-init).

Arguments:

• <port>: Add a TCP port (e.g., 80, 8080)
• <port>/udp: Add a UDP port (e.g., 51820/udp)
• remove <port>: Remove a TCP port
• remove <port>/udp: Remove a UDP port

How ports work in this project

Ports are controlled by two variables in terraform/environments/oci-prod/variables.tf:

• additional_tcp_ports (default: [80, 443])
• additional_udp_ports (default: [])

These feed into two places via locals in main.tf:

1. VCN security list — network-level firewall
2. Cloud-init template — instance-level iptables rules

When enable_public_access = false, both lists are forced empty regardless of these variables.

Steps

1. Read terraform/environments/oci-prod/oci-prod.auto.tfvars to check current port settings
2. If no port override exists in tfvars, the defaults from variables.tf apply
3. Add or remove the port from the appropriate list in oci-prod.auto.tfvars
4. Warn the user that cloud-init changes (iptables) require instance recreation to take effect, while security list changes apply immediately via terraform apply
5. Ask if they want to run terraform plan to preview the change