34: OCI: NW ‐ Manual Creation of Hub VCN. Hub Public Subnet, Hub subnet‐Security list - pavankumarchittajallu/OCI_DOC GitHub Wiki

Step-by-Step Process: OCI Hub Networking Components.

1. Create the Hub VCN

  1. Go to the OCI Console and navigate to the main menu (≡) > Networking > Virtual Cloud Networks.
  1. Click Create VCN.
  1. Enter a name for your Hub VCN (e.g., "Hub-VCN").
  1. Specify the IPv4 CIDR block for the VCN (e.g., 10.0.0.0/16).
  1. Choose the compartment where the VCN resides.
  1. Click Create VCN. Wait until status shows as “Available”

2. Create the Hub Public Subnet

  1. Select the newly created Hub VCN from the Virtual Cloud Networks list.
  1. Go to the Subnets tab and click Create Subnet.
  1. Enter a name for your public subnet (e.g., “Hub-Public-Subnet”).
  2. Confirm the compartment.
  1. Choose Subnet Type: “Regional” (recommended) ensures the subnet spans all availability domains.
  1. Specify the CIDR Block for the subnet (e.g., 10.0.1.0/24).
  1. Set Subnet Access to “Public Subnet”.
  1. In Route Table, select the appropriate route table (or leave default for now).
  1. In Security Lists, select the security list you plan to use (you can update later, see step 3).
  1. Click Create Subnet

3. Manually Create and Assign a Security List

A. Creating the Security List

  1. With your Hub VCN still selected, find the Security Lists section.
  1. Click Create Security List.
  1. Enter a friendly name (e.g., “Hub-Public-SL”).
  2. Choose the correct compartment.
  1. Add Ingress Rule(s), e.g.:
    • Source CIDR: 0.0.0.0/0
    • IP Protocol: TCP
    • Source Port Range: (leave blank for all)
    • Destination Port Range: 22 (for SSH) or others as required
  1. Add Egress Rule(s), e.g.:
    • Destination CIDR: 0.0.0.0/0
    • IP Protocol: All Protocols
  1. Click Create Security List

B. Assign Security List to Subnet

  1. Go back to the Subnets tab in the VCN.
  1. Click the desired subnet (“Hub-Public-Subnet”).
  1. Click Edit to modify the Security Lists.
  1. Add your new custom security list (“Hub-Public-SL”) and remove the default one if you prefer.
  1. Save changes.