Brocade MLX Series and Brocade NetIron XMR Diagnostic Guide ...

PIM DM and PIM SM 8• If you want to continue to use PIM DM V1 on an interface, you must change the version, andthen save the configuration. This does not mean you can run different PIM versions on devicesthat are connected to each other. The devices must run the same version of PIM. If you want toconnect a device running PIM to a device that is running PIM V1, you must change the PIMversion on the device to V1 (or change the version on the device to V2, if supported).• When PIM routing is enabled, the line rate for receive traffic is reduced by about 5 percent. Thereduction occurs due to overhead from the VLAN multicasting feature, which PIM routing uses.This behavior is normal and does not indicate a problem with the device.• You do not need to enable IP multicast routing globally when configuring PIM SM.• It is recommended that you configure the same device as both the BSR and the RP.• It is possible to configure the device as only a candidate BSR or RP, but it is recommended thatyou configure the same interface on the same device as both a BSR and an RP.• Specify the same IP address as the RP on all PIM SM routers within the PIM SM domain. Makesure the router is on the backbone or is otherwise well connected to the rest of the network.• Use the same join or prune message interval on all the PIM SM routers in the PIM SM domain.If the routers do not all use the same timer interval, the performance of PIM SM can beadversely affected.Common diagnostic scenarios• The following PIM SM error appears:ERROR - cannot enable PIM sparse or DVMRP on an interface.This issue is resolved by upgrading the software version to reflect the latest patches andversions.• Specific multicast sources are not being forwarded properly.The dmzo router was directed to an incorrect rpf. After modifying the configuration, theproblem is resolved.• Enabling IP PIM-SPARSE caused high CPU usage.This can occur when the device runs out of CAM due to large amounts of multicast trafficflooding the CAM. Make sure the device is using the most current patch of the software, andcontact Brocade Technical Support for assistance.Brocade MLX Series and Brocade NetIron XMR Diagnostic Guide 29553-1002426-02