kubernetes/kops · error

error deleting subnet: %v

Error message

error deleting subnet: %v

What it means

deleteSubnet deletes a Neutron subnet by ID inside a RetryWithBackoff(deleteBackoff) loop, tolerating 404 (already gone) via isNotFound. Any other failure is wrapped as "error deleting subnet: %v" and retried until backoff is exhausted. This typically means the subnet still has dependents or the API rejected the delete.

Source

Thrown at upup/pkg/fi/cloudup/openstack/subnet.go:113

	})
	if err != nil {
		return s, err
	} else if done {
		return s, nil
	} else {
		return s, wait.ErrWaitTimeout
	}
}

func (c *openstackCloud) DeleteSubnet(subnetID string) error {
	return deleteSubnet(c, subnetID)
}

func deleteSubnet(c OpenstackCloud, subnetID string) error {
	done, err := vfs.RetryWithBackoff(deleteBackoff, func() (bool, error) {
		err := subnets.Delete(context.TODO(), c.NetworkingClient(), subnetID).ExtractErr()
		if err != nil && !isNotFound(err) {
			return false, fmt.Errorf("error deleting subnet: %v", err)
		}
		if isNotFound(err) {
			return true, nil
		}
		return false, nil
	})
	if err != nil {
		return err
	} else if done {
		return nil
	} else {
		return wait.ErrWaitTimeout
	}
}

func (c *openstackCloud) GetExternalSubnet() (subnet *subnets.Subnet, err error) {
	return getExternalSubnet(c, c.extSubnetName)
}

View on GitHub (pinned to 4c8573c808)

Solutions

1. Check the wrapped error for 409 conflict and delete dependent ports/router interfaces first: `openstack port list --subnet <id>`,`openstack router remove subnet`
2. Ensure no instances/load balancers still use the subnet
3. Retry `kops delete cluster` after dependents are removed
4. Verify project RBAC allows subnet deletion

// Ensure no ports remain on the subnet before delete
out, err := exec.Command("openstack", "port", "list", "--subnet", subnetID, "-f", "value", "-c", "ID").Output()
if err == nil && len(strings.TrimSpace(string(out))) > 0 {
	log.Fatalf("subnet %s still has ports: %s", subnetID, string(out))
}

err := deleteSubnet(cloud, subnetID)
if err != nil {
	if strings.Contains(err.Error(), "409") || strings.Contains(err.Error(), "conflict") {
		// detach router interfaces / delete ports, then retry
	}
	return err
}

When it happens

Trigger: Subnet has attached ports (instances, routers, LBs) so Neutron returns 409 conflict; RBAC denies deletion; or Neutron is unhealthy.

Common situations: Tearing down a cluster where VMs/ports were not yet deleted, a router interface still attached to the subnet, or manual resources sharing the subnet blocking kops destroy.

Related errors

• error listing subnets in network %q: %v
• error retrieving subnet with id %s: %v
• error listing subnets: %v
• error extracting subnets from pages: %v
• error retrieving subnet: %v

AI-assisted analysis of kubernetes/kops@4c8573c808 (2026-09-05). Data as JSON: /api/errors/62fcf743b9e843b4. Report an issue: GitHub.