H3C Technologies H3C S10500 Series Switches - Manual (Page 128)

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NOTE:
•
The maximum interval for sending RA messages should be less than (or equal to) the router lifetime in
RA messages, so the router can be updated through an RA message before expiration.
• The values of the NS retransmission timer and the reachable time configured for an interface are sent to
hosts via RA messages. Furthermore, this interface sends NS messages at the interval of the NS
retransmission timer and considers a neighbor reachable within the reachable time.
Configuring the maximum number of attempts to send an NS
message for DAD
An interface sends an 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 the interface still does not receive a response after the number of
sent attempts reaches the threshold (specified with the ipv6 nd dad attempts command), the acquired
address is considered usable.
Follow these steps to configure the attempts to send an NS message for DAD:
To do… Use the command… Remarks
Enter system view system-view —
Enter interface view
interface interface-type
interface-number
—
Configure the number of attempts
to send an NS message for DAD
ipv6 nd dad attempts value
Optional
1 by default. When the value
argument is set to 0, DAD is
disabled.
Configuring PMTU discovery
Configuring a static PMTU for a specified IPv6 address
You can configure a static PMTU for a specified destination IPv6 address. When a source host sends a
packet 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 of the two values, the host
fragments the packet according to the smaller value.
Follow these steps to configure a static PMTU for a specified IPv6 address:
To do… Use the command… Remarks
Enter system view system-view —
Configure a static PMTU for a
specified IPv6 address
ipv6 pathmtu [ vpn-instance
vpn-instance-name ] ipv6-address
[ value ]
Required
Not configured by default