Quanta Cloud Technology QuantaMesh QNOS5, Руководство по настройке

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5. Change the region name so that all the bridges that want to be part of the same region can form the
region.
(QCT) (Config)#spanning-tree configuration name QCT
6. (Switch A only) Make Switch A the Regional Root for MSTI 1 by configuring a higher priority for MST ID 10.
(QCT) (Config)#spanning-tree mst priority 10 12288
7. (Switch A only) Change the priority of MST ID 20 to ensure Switch C is the Regional Root bridge for this
MSTI.
(QCT) (Config)#spanning-tree mst priority 20 61440
8. (Switch C only) Change the priority of Switch C to force it to be the root bridge for MST 20.
(QCT) (Config)#spanning-tree mst priority 20 12288
(QCT) (Config)#exit
3.9. IGMP Snooping
IGMP Snooping is a layer-2 feature that allows the switch to dynamically add or remove ports from IP
multicast groups by listening to IGMP join and leave requests. By “snooping” the IGMP packets transmitted
between hosts and routers, the IGMP Snooping feature enables the switch to forward IP multicast traffic
more intelligently and help conserve bandwidth.
Based on the IGMP query and report messages, the switch forwards traffic only to the ports that request
the multicast traffic. This prevents the switch from broadcasting the traffic to all ports and possibly
affecting network performance. The switch uses the information in the IGMP packets as they are being
forwarded throughout the network to determine which segments should receive packets directed to the
group address.
3.9.1. IGMP Snooping Querier
When PIM and IGMP are enabled in a network with IP multicast routing, the IP multicast router acts as the
IGMP querier. However, if the IP-multicast traffic in a VLAN needs to be Layer 2 switched only, an IP-
multicast router is not required. The IGMP Snooping Querier can perform the IGMP snooping functions on
the VLAN.
Without an IP-multicast router on a VLAN, you must configure another switch as the IGMP querier so that it
can send queries.
When the IGMP snooping querier is enabled, the IGMP snooping querier sends out periodic IGMP queries
that trigger IGMP report messages from the switch that wants to receive IP multicast traffic. The IGMP
snooping feature listens to these IGMP reports to establish appropriate forwarding.
3.9.2. Configuring IGMP Snooping
This example configures IGMP snooping on the switch to limit multicast traffic and to allow L2 multicast
forwarding on a single VLAN. The IP-multicast traffic in VLAN 100 needs to be Layer 2 switched only, so the
IGMP snooping querier is enabled on the switch to perform the IGMP snooping functions on the VLAN, if