270
NOTE:
Even though an MLD snooping proxy is a host from the perspective of its upstream device, the MLD
membership report suppression mechanism for hosts does not take effect on it. For more information
about the MLD report suppression mechanism for hosts, see "Configuring MLD (available only on the
S5500-E
I)."
Figure 69 Network diagram
As shown in Figure 69, Switch A works as an MLD snooping proxy. As a host from the perspective of the
querier Router A, Switch A represents its attached hosts to send their membership reports and done
messages to Router A.
Table 8 de
scribes how an MLD snooping proxy processes MLD messages.
Table 8 MLD message processing on an MLD snooping proxy
MLD messa
e Actions
General query
When receiving an MLD general query, the proxy forwards it to all ports but the receiving
port. In addition, the proxy generates a report according to the group memberships that it
maintains and sends the report out of all router ports.
Multicast-addres
s-specific query
In response to the MLD group-specific query for a certain IPv6 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
When receiving a report for an IPv6 multicast group, the proxy looks up the multicast
forwarding table for the entry for the multicast group.
• If a forwarding entry matches the IPv6 multicast group, and contains the receiving port
as a dynamic member port, the proxy restarts the aging timer for the port.
• If a forwarding entry matches the IPv6 multicast group but does not contain the receiving
port, the proxy adds the port to the forwarding entry as a dynamic member port and
starts an aging timer for the port.
• If no forwarding entry matches the IPv6 multicast group, the proxy creates a forwarding
entry for the group, adds the receiving port to the forwarding entry as a dynamic
member port, and starts an aging timer for the port.
Then, the switch sends the report to the group out of all router ports.
To Next Page
Loading...
