The ipv6 icmp too-big-rate-limit command enables the suppression of ICMPv6 Packet Too Big messages.
The undo ipv6 icmp too-big-rate-limit command disables the suppression of ICMPv6 Packet Too Big messages.
By default, a device is enabled with the suppression of ICMPv6 Packet Too Big messages.
Usage Scenario
If the size of an IPv6 packet sent by the source node exceeds the link MTU of the outbound interface on a network node, the network node replies with an ICMPv6 Packet Too Big message that contains the MTU value of the outbound interface on the network node.
If the source node receives excessive ICMPv6 Packet Too Big messages, much memory will be used, and the system performance will be affected. By default, the system is enabled with the suppression of ICMPv6 Packet Too Big messages by processing only 50 ICMPv6 Packet Too Big messages within 1 second. If a large number of path MTU requests exist within a short period of time, run the undo ipv6 icmp too-big-rate-limit command to disable the suppression of ICMPv6 Packet Too Big messages.