#Automatic Interconnection of Underlay and Overlay Subnets

If a cluster has both Underlay and Overlay subnets, by default, Pods under the Overlay subnet can access Pods' IPs in the Underlay subnet through a gateway using NAT. However, Pods in the Underlay subnet need to configure node routing to access Pods in the Overlay subnet.

To achieve automatic interconnection between Underlay and Overlay subnets, you can manually modify the YAML file of the Underlay subnet. Once configured, Kube-OVN will also use an additional Underlay IP to connect the Underlay subnet and the ovn-cluster logical router, setting the corresponding routing rules to enable interconnection.

#Steps

1. Go to Platform Management.

2. In the left navigation bar, click on Cluster Management > Resource Management.

3. Enter Subnet to filter resource objects.

4. Click on ⋮ > Update next to the Underlay subnet to be modified.

5. Modify the YAML file, adding the field u2oInterconnection: true in the Spec.

6. Click Update.

Note: Existing compute components in the Underlay subnet need to be recreated for the changes to take effect.