configure iproute add blackhole ipv6 default

configure iproute add blackhole ipv6 default {vr vr_name} {multicast-only | unicast-only}


Adds a default blackhole route to the routing table. All traffic destined for an unknown IPv6 destination is silently dropped.

Syntax Description

vr_name Specifies the VR or VRF to which the route is added.
multicast-only Specifies only multicast traffic for the route.
unicast-only Specifies only unicast traffic for the route.


If you do not specify a VR or VRF, the current VR context is used.

Usage Guidelines

While a default route is for forwarding traffic destined to an unknown IPv6 destination, and a blackhole route is for discarding traffic destined to a specified IPv6 destination, a default blackhole route is for discarding traffic to the unknown IPv6 destination.

Using this command, all traffic with an unknown destination is discarded.

The default blackhole route is treated like a permanent entry in the event of a switch reset or power off/on cycle. The default blackhole route‘s origin is "b" or "blackhole" and the gateway IPv6 address for this route is ::.

The packets are silently discarded. In other words, no ICMP message is sent to indicate that the packets are discarded.


The following example adds a blackhole default route into the routing table:

configure iproute add blackhole ipv6 default


This command was first available in ExtremeXOS 10.1.

Support for IPv6 was added in ExtremeXOS 11.2.

Platform Availability

This command is available on the platforms listed for the IPv6 unicast routing feature in the Switch Engine 32.2 Feature License Requirements document.