Configure a Black Hole Static Route

Create a black hole static route to the destination that a router advertises to avoid routing loops when aggregating or injecting routes to other routers.

Before you begin

To perform this procedure on a non-default VRF, you must first change the VRF instance. For information about how to use EDM for a non-default VRF, see Select and Launch a VRF Context View. All parameters might not be available in non-default VRFs.

About this task

If an existing black hole route is enabled, you must first delete or disable it before you can add a regular static route to that destination.

Note

Note

Only black hole routes that belong to the static type protocol are supported. An inter-VRF black hole route is not installed in the routing table of the destination VRF on the same switch.

Procedure

  1. In the navigation pane, expand Configuration > IP.
  2. Select IP.
  3. Select the Static Routes tab.
  4. Select Insert.
  5. In the OwnerVrfId check box, select the appropriate VRF ID.
  6. In the Dest field, enter the IP address.
  7. In the Mask field, enter the network mask.
  8. In the NextHop field, type 255.255.255.255.

    To create a black hole static route, you must configure the NextHop address to 255.255.255.255.

  9. Select the enable option.
  10. In the Metric box, type the HopOrMetric value.
  11. In the Preference check box, select the route preference.

    When you specify a route preference, be sure to appropriately configure the preference so that when the black hole route is used, it is elected as the best route.

  12. Select Insert.
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