Unable to Attach Floating IP to Instance: "External Network Not Reachable from Subnet
Problem
- A floating IP is unable to be attached to an instance.
- The following error is observed in Clarity UI when attempting to attach the floating IP.
Environment
- Platform9 Managed OpenStack - All Versions
- Neutron
Causes
- No router has been created and associated with the subnet.
- Router associated with subnet, but isn't connected to external network.
- Router isn't connected to internal subnet, but has an external gateway.
Resolution
No Router Has Been Created
- For guidance with creating a router, refer to Create Router in our networking guide.
Subnet Not Associated with Router
- In Clarity UI, navigate to "Networks" > "Routers".
- Click on the desired router.
- Note: Ensure you are scoped to the appropriate tenant to be able to view the router.
- Navigate to the "Interfaces" tab.
- Click "+ Create New Interface".
- Select the desired subnet.
- Click "Add Interface".
Router Has No External Gateway
- In Clarity UI, navigate to "Networks" > "Routers".
- Click on the radio button for the desired router.
- Click "Edit Router".

Screen_Shot_2019-12-18_at_9.03.06_AM.png
- Select an external network from the "Set External Network" dropdown.

Screen_Shot_2019-12-18_at_9.03.28_AM.png
- Click "Update Router".
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