Configuring Parameters Related To An Ra Message - H3C S7500E Series Operation Manual

Operation Manual – IPv6 Configuration
H3C S7500E Series Ethernet Switches

1.4.3 Configuring Parameters Related to an RA Message

You can configure whether the interface sends an RA message, the interval for sending
RA messages, and parameters in RA messages. After receiving an RA message, a
host can use these parameters to perform corresponding operations.
configurable parameters in an RA message and their descriptions.
Table 1-4 Parameters in an RA message and their descriptions
Parameters
Cur hop limit
Prefix information
options
M flag
O flag
Router lifetime
Retrans timer
Reachable time
When sending an IPv6 packet, a host uses the value of this
parameter to fill the Cur Hop Limit field in IPv6 headers.
Meanwhile, the value of this parameter is equal to the value
of the Cur Hop Limit field in response messages of the
device.
After receiving the prefix information advertised by the
device, the hosts on the same link can perform stateless
autoconfiguration operations.
This field determines whether hosts use the stateful
autoconfiguration to acquire IPv6 addresses.
If the M flag is set to 1, hosts use the stateful
autoconfiguration to acquire IPv6 addresses. Otherwise,
hosts use the stateless autoconfiguration to acquire IPv6
addresses, that is, hosts configure IPv6 addresses
according to their own link-layer addresses and the prefix
information issued by the router.
This field determines whether hosts use the stateful
autoconfiguration to acquire information other than IPv6
addresses.
If the O flag is set to 1, hosts use the stateful
autoconfiguration (for example, DHCP server) to acquire
information other than IPv6 addresses. Otherwise, hosts use
the stateless autoconfiguration to acquire information other
than IPv6 addresses.
This field is used to set the lifetime of the router that sends
RA messages to serve as the default router of hosts.
According to the router lifetime in the received RA
messages, hosts determine whether the router sending RA
messages can serve as the default router of hosts.
If the device fails to receive a response message within the
specified time after sending an NS message, the device will
retransmit it.
After the neighbor reachability detection shows that a
neighbor is reachable, the device considers the neighbor is
reachable within the reachable time. If the device needs to
send a packet to a neighbor after the reachable time expires,
the device will again confirm whether the neighbor is
reachable.
1-16
Chapter 1 IPv6 Basics Configuration
Table 1-4
Description
lists the