The ipv6 icmp host-unreachable send command enables transmitting the ICMPv6 host-unreachable packets.
The undo ipv6 icmp host-unreachable send command disables transmitting the ICMPv6 host-unreachable packets.
By default, disable transmitting the ICMPv6 host-unreachable packets.
Heavy network traffic load (for example, sending ICMPv6 host-unreachable packets frequently) increases the processing load and degrades the device performance. You can run the undo ipv6 icmp host-unreachable send command to disable the interface from sending ICMPv6 host-unreachable packets, which improves network performance and security.