Configuring Pmtu Discovery - 3Com Switch 4800G 24-Port Configuration Manual

Configuring the Number
of Attempts to Send an
NS Message for DAD
Configuring PMTU
Discovery
Configuring a Static
PMTU for a Specified
IPv6 Address
Configuring the Aging
Time for PMTU
To do...
Set the reachable time
c
CAUTION: The maximum interval for sending RA messages should be less than or
equal to the router lifetime in RA messages.
An interface sends a neighbor solicitation (NS) message for DAD after acquiring an
IPv6 address. If the interface does not receive a response within a specified time
(determined by the ipv6 nd ns retrans-timer command), it continues to send an
NS message. If it still does not receive a response after the number of attempts to
send an NS message reaches the maximum, the acquired address is considered
available.
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
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
After the MTU of the path from the source host to the destination host is
dynamically determined (refer to "IPv6 PMTU Discovery" on page 507), the source

Configuring PMTU Discovery

Use the command...
ipv6 nd nud
reachable-time value
Use the command...
system-view
interface interface-type
interface-number
ipv6 nd dad attempts value Optional
Use the command...
system-view
ipv6 pathmtu ipv6-address
[ value ]
513
Remarks
Optional
By default, the neighbor
reachable time on the local
interface is 30,000
milliseconds and the
Reachable Timer field in RA
messages is 0.
Remarks
-
-
1 by default. When the value
argument is set to 0, DAD is
disabled.
Remarks
-
Required
By default, no static PMTU is
configured.