HP 4500G PWR 24-Port, Руководство по настройке

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Introduction to multicast traceroute packets
A multicast traceroute packet is a special IGMP packet, which differs from common IGMP packets in
that its IGMP Type field is set to 0x1F or 0x1E and that its destination IP address is a unicast address.
There are three types of multicast traceroute packets:
z
Query, with the IGMP Type field set to 0x1F,
z
Request, with the IGMP Type field set to 0x1F, and
z
Response, with the IGMP Type field set to 0x1E.
Process of multicast traceroute
1) The querier sends a query to the last-hop router.
2) Upon receiving the query, the last-hop router turns the query packet into a request packet by
adding a response data block containing its interface addresses and packet statistics to the end of
the packet, and forwards the request packet via unicast to the previous hop for the given multicast
source and group.
3) From the last-hop router to the multicast source, each hop adds a response data block to the end of
the request packet and unicasts it to the previous hop.
4) When the first-hop router receives the request packet, it changes the packet type to indicate a
response packet, and then sends the completed packet via unicast to the multicast traceroute
querier.
Configuration Task List
Complete these tasks to configure multicast routing and forwarding:
Task Remarks
Enabling IP Multicast Routing Required
Configuring Multicast Static Routes Optional
Configuring a Multicast Routing Policy Optional
Configuring a Multicast Forwarding Range Optional
Configuring the Multicast Forwarding Table Size Optional
Configuring Multicast
Routing and Forwarding
Tracing a Multicast Path Optional
IP multicast does not support the use of secondary IP address segments. Namely, multicast can be
routed and forwarded only through primary IP addresses, rather than secondary addresses, even if
configured on interfaces.
For details about primary and secondary IP addresses, refer to
IP Addressing Configuration
in the
IP
Services Volume
.
Enabling IP Multicast Routing
Before configuring any Layer 3 multicast functionality, you must enable IP multicast routing.