Instance Unreachable After Attaching Second Neutron Port

Problem

After attaching a second Neutron port to an existing instance, the instance becomes unreachable.

Environment

• Platform9 Managed OpenStack - All versions

• Neutron

• CentOS

Cause

If the second Neutron network you attached to your OpenStack instance has a default gateway, it will override the instances’ existing default gateway.

Resolution

1. Run the following command to use the gateway device from the first Neutron port.

2. Restart the instance if the network connectivity is not restored.