Configuring Pmtu Discovery; Configuring The Interface Mtu; Configuring A Static Pmtu For A Specified Ipv6 Address - 3Com MSR 50 Series Configuration Manual

670 C 46: IP 6 B
HAPTER V
Configuring PMTU
Discovery
Configuring the
Interface MTU
Configuring a Static
PMTU for a Specified
IPv6 Address
C
ASICS ONFIGURATION
send an NS message reaches the maximum, the acquired address is considered
usable.
Follow these steps to configure the attempts to send an NS message for DAD:
To do...
Enter system view
Enter interface view
Configure the number of
attempts to send an NS
message for DAD
IPv6 routers do not support packet fragmentation. After an IPv6 router receives an
IPv6 packet, if the packet size is greater than the MTU of the forwarding interface,
the router will discard the packet. Meanwhile, the router sends the MTU to the
source host through an ICMPv6 packet - Packet Too Big message. The source host
fragments the packet according to the MTU and resends it. To reduce the extra
flow overhead resulting from packets being discarded, a proper interface MTU
should be configured according to the actual networking environment.
Follow these steps to configure the interface MTU:
To do...
Enter system view
Enter interface view
Configure the interface MTU
You can configure a static PMTU for a specified destination IPv6 address. When a
source host sends packets through an interface, it compares the interface MTU
with the static PMTU of the specified destination IPv6 address. If the packet size is
larger than the smaller one between the two values, the host fragments the
packet according to the smaller value.
Follow these steps to configure a static PMTU for a specified address:
To do...
Enter system view
Configure a static PMTU for a
specified IPv6 address
Use the command...
system-view
interface interface-type
interface-number
ipv6 nd dad attempts value Optional
Use the command...
system-view
interface interface-type
interface-number
ipv6 mtu mtu-size
Use the command...
system-view
ipv6 pathmtu ipv6-address
[ value ]
Remarks
-
-
1 by default. When the value
argument is set to 0, DAD is
disabled.
Remarks
-
-
Optional
1,500 bytes by default.
Remarks
-
Required
By default, no static PMTU is
configured.