Points to Note When Using the WXR100, WX1200, WX4400, or WX2200

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Distributed MAP Best Practice When Using STP

A Distributed MAP is a leaf device. You need not enable STP on the port directly connected to the MAP.

If Spanning Tree Protocol (STP) is enabled on the port that is directly connected to a Distributed MAP, you might need to change the STP configuration on the port to allow the MAP to boot.

STP on a port directly connected to a Distributed MAP can prevent the MAP from booting.

Use IGMP Snooping EffectivelyUsing IGMP (11909, 12863, 12866)

MSS supports the Internet Engineering Task Force (IETF) draft draft-ietf-magma-snoopfor controlling the forwarding of IP multicast traffic by a Layer 2 switch. The draft mandates the use of a 0.0.0.0 source IP address if no IP address is available on the switch for the subnet. However, some multicast routers and even other Layer 2 switches report errors in the presence of the 0.0.0.0 source IP address.

Apply the following methods to use IGMP snooping effectively:

■Set IP addresses on all VLAN interfaces. This straightforward workaround prevents most known issues. If querier functionality might be needed, ensure that the IP address of the WX switch VLAN is higher than the address of any multicast router servicing the same subnet.

■Consider disabling IGMP proxy reporting. The IGMP proxy reporting function is enabled by default, but some multicast routers do not accept

reports using a 0.0.0.0 source IP address. In this case, either assign an IP address to the VLAN interface on the WX switch or disable IGMP proxy reporting. To disable proxy reporting, use the command set igmp proxy-report disable.

Disabling proxy reporting can increase IGMP overhead traffic to the multicast router.

■Enable the IGMP querier only if needed. The IGMP pseudo-querier function is disabled by default. Enable it only if the source of a multicast stream is on a subnet the WX switch is also connected to. If this is the case, you must assign an IP address to the VLAN interface. The IP address must be higher than the IP address of the querier multicast router on the same subnet. To enable the IGMP pseudo-querier, use the command set igmp querier enable.

■Disable multicast router discovery. This multicast router solicitation protocol (part of draft-ietf-magma-snoop) is known to cause error messages with other IGMP snooping switches and multicast routers. To disable the protocol, use the command set igmp mrsol disable. (The protocol is disabled by default in the current software version.)

User ACLs Require Explicit Source and Destination Addresses

A user ACL is an ACL that is applied to a specific user- name. You can apply ACLs to a user’s inbound or outbound wireless traffic. For a user ACL to take effect, you must explicitly set both the source and destination addresses in the ACL.