HPE 5820X Series, Руководство по настройке

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Figure 13 Network diagram
As shown in Figure 13 , Switch A works as an IGMP snooping proxy. As a host from the perspective of
the querier Router A, Switch A represents its attached hosts to send membership reports and leave
messages to Router A.
Table 6 lists the IGMP messages and their processing on an IGMP snooping
proxy.
Table 6 IGMP message processing on an IGMP snooping proxy
IGMP message Actions
General query
When receiving an IGMP general query, the proxy forwards it to all ports except the port
that receive the query. In addition, the proxy generates a report according to the group
membership that it maintains and sends the report out of all router ports.
Group-specific
query
In response to the IGMP group-specific query for a certain multicast group, the proxy
sends the report to the group out of all router ports if the forwarding entry for the group
still contains a member port.
Report
After receiving a report for a multicast group, the proxy looks up the multicast
forwarding table for a matching forwarding entry.
•
If a match is found and the matching entry contains the receiving port as a dynamic
member port, the proxy restarts the aging timer for the port.
•
If a match is found but the matching entry does not contain the receiving port, the
proxy adds the port to the forwarding entry. It also marks the port as a dynamic
member port and starts an aging timer for the port.
•
If no match is found, the proxy creates a forwarding entry for the multicast group
with the receiving port as an outgoing interface. It also marks the port as a dynamic
member port and starts an aging timer for the port.
Leave
In response to an IGMP leave message for a multicast group, the proxy sends a
group-specific query out of the receiving port. After making sure that no member port is
contained in the forwarding entry for the multicast group, the proxy sends a leave
message to the group out of all router ports.
Host A
Receiver
Host B
Host C
Receiver
IGMP Querier
Router A
Proxy & Querier
Switch A
Query from Router A
Report from Switch A
Query from Switch A
Report from Host
IP network