3com S7906E Instruccion De Instalación

 

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For devices that support both drop-unknown and mld-snooping drop-unknown commands at 

the same time, the configuration made in MLD snooping view and the configuration made in VLAN 

view are mutually exclusive. Namely, after this function is enabled in MLD snooping view, it cannot 

be enabled or disabled in VLAN view, and vice versa.  

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Configurations made in MLD snooping view are effective for all VLANs, while configurations made 

in VLAN view are effective only for ports belonging to the current VLAN.  

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If the function of dropping IPv6 multicast packets is globally enabled in MLD snooping view, IPv6 

multicast packets sent to MLD snooping-enabled VLANs are all dropped. The IPv6 multicast 

packets mentioned here include both IPv6 multicast data packets and protocol packets, such as 

IPv6 PIM, OSPFv3, and IPv6 VRRP messages.  

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After the function of dropping unknown IPv6 multicast data packets is enabled in VLAN view, the 

switch forwards unknown IPv6 multicast data packets to its router ports, if any, instead of flooding 

them in the VLAN. Otherwise, if no router ports exist, the switch drops these IPv6 multicast data 

packets. Currently, the S7900E supports processing unknown IPv6 multicast data packets 

destined for up to 1000 IPv6 unknown multicast addresses at a time. The switch floods excessive 

unknown IPv6 multicast data packets directly.  

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The S7900E supports the function of dropping unknown IPv6 multicast data packets configuring in 

up to 500 VLANs. 

 

When a Layer 2 device receives an MLD report from an IPv6 multicast group member, the Layer 2 

device forwards the message to the Layer 3 device directly connected with it. Thus, when multiple 

members belonging to an IPv6 multicast group exist on the Layer 2 device, the Layer 3 device directly 

connected with it will receive duplicate MLD reports from these members.  

With the MLD report suppression function enabled, within a query interval, the Layer 2 device forwards 

only the first MLD report of an IPv6 group to the Layer 3 device and will not forward the subsequent 

MLD reports from the same multicast group to the Layer 3 device. This helps reduce the number of 

packets being transmitted over the network. 

Follow these steps to configure MLD report suppression:  

Enter system view 

— 

Enter MLD snooping view 

— 

Enable MLD report 
suppression  

Optional 

Enabled by default