Internet Protocol version 6 (IPv6), also called IP Next Generation (IPng), is a standard network protocol of the second generation. It is designed by the Internet Engineering Task Force (IETF) as an upgraded version of IPv4 and makes up the defects of IPv4.
If multiple addresses are configured on an interface of the device, the IPv6 address selection policy table can be used to select source and destination addresses for packets.
This section describes how to configure conflicting IPv6 addresses for different interfaces after the IPv6 address conflict detection function is disabled as well as to configure the preemption function so that conflicting IPv6 addresses take effect on interfaces with higher priorities.
In ICMPv6 message control, the token bucket algorithm is adopted, and one token represents one ICMPv6 message. Tokens are placed in the virtual bucket at fixed intervals until the capacity of the token bucket reaches the upper threshold. If the number of ICMPv6 messages exceeds the upper threshold, extra messages are discarded.
After IPv6 is enabled on a device, the device does not permit IPv6 packets whose first fragment carries an incomplete header by default. To use IPv6 packets whose first fragment carries an incomplete header in special scenarios, configure the device to permit such IPv6 packets.
To improve device performance and prevent attacks, run the ipv6 reassembling timeout command to set a proper reassembly timeout period for IPv6 fragments so that IPv6 fragments that have waited for reassembly for a long time are promptly aged.
To easily observe the inbound interface of a device along the path, you can configure the IPv6 address of the inbound interface for forwarding packets as the source address of an ICMPv6 Time Exceeded message.
After a PMTU is configured, devices on a network send packets based on the same MTU so that packets do not need to be fragmented in the transmission process and the burden of intermediate devices is reduced. Therefore, network resources are efficiently utilized to achieve the optimal traffic throughput.