User's Manual

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All interfaces have a default IPv6 MTU. If the length of an IPv6 packet exceeds MTU, the router will
fragment this IPv6 packet.
To set IPv6 MTU on a specific interface, run the following command in interface configuration mode:
COMMAND
Purpose
ipv6 mtu bytes Sets IPv6 MTU on an interface.
Setting IPv6 redirection
Sometimes, the route selected by the host is not the best one. In this case, when a switch receives a
packet from this route, the switch will transmit, according to the routing table, the packet from the interface
where the packet is received, and forward it to another router which belongs to the same network segment
with the host. Under this condition, the switch will notify the source host of sending the packets with the
same destination address to another router directly, not by way of the switch itself. The redirection packet
demands the source host to replace the original route with the more direct route contained in the redirection
packet. The operating system of many hosts will add a host route to the routing table. However, the switch
more trusts the information getting from the routing protocol and so the host route will not be added
according to this information.
IPv6 redirection is opened by default. However, if a hot standby router protocol is configured on an interface,
IPv6 redirection is automatically closed. If the hot standby router protocol is canceled, this function will not
automatically opened.
To open IPv6 redirection, run the following command:
COMMAND
Purpose
ipv6 redirects Allows IPv6 to transmit the redirection
packets.
Setting IPv6 destination unreachablity
In many cases, the system will automatically transmit the destination-unreachable packets. Users can
close this function. If this function is closed, the system will not transmit the ICMP unreachable packets.
To enable this function, run the following command:
COMMAND
Purpose
ipv6 unreachables Allows IPv6 to transmit the destination
unreachable packets.
Setting IPv6 ACL
Users can use ACL to control the reception and transmission of packets on a VLAN interface. If you
introduce ACL on a VLAN interface in global configuration mode and designate the filtration's direction, the
IPv6 packets will be filtered on this VLAN interface.
To filter the IPv6 packets, run the following command in interface configuration mode.