3Com SuperStack II 3300, Руководство пользователя

Страница: 83 / 172

Enabling and Disabling ICMP Router Discovery 83
2 Enter the multicast source address.
Enter multicast group address [255.255.255.255]:
3 Enter the multicast group address. The DVMRP status is displayed.
Table 18 describes the fields in the multicast cache display.
Enabling and
Disabling ICMP
Router Discovery
The Internet Control Message Protocol (ICMP) Router Discovery protocol
(RFC 1256) allows an appropriately configured end station to locate one
or more routers on the LAN to which it is attached. The end station then
automatically installs a default route to each of the routers running ICMP
Router Discovery. You do not need to manually configure a default route.
ICMP redirect messages will subsequently channel the IP traffic to the
correct router.
Only certain workstations can be configured to work with the ICMP
Router Discovery protocol. Refer to the documentation for your
workstation to determine whether it can be configured to work with this
protocol.
Table 18 Multicast Cache Display Fields
Field Description
Origin The source of the incoming packets. Entries preceded by an
angle bracket (>) indicate a multicast subnetwork. Entries
without an angle bracket are multicast routers within the
subnetwork that immediately precedes them in the table
.
Mcast-group The destination multicast group.
CTmr Cache timer, which is the amount of time that a cache
entry has to remain in the cache.
Age Number of seconds (s), minutes (m), or hours (h) that the
cache entry has been in existence.
PTmr The time remaining, in seconds (s), minutes (m), or hours
(h), before another prune message will be sent to the
network.
In-If Interface number on which that gateway is connected.
Traffic is expected to originate from this interface.
T
represents the tunnel;
P
denotes that a prune message has
been sent to this tunnel.
Out-Ifs Set of interfaces out of which the traffic will be flooded.
Ix
represents the interface.