Dell Force10 E600i FTOS Version 8.4.1.5 Configuration Guide for ExaScale - Page 718

www.dell.com | support.dell.com Set a Threshold for Switching to the SPT e Set a Threshold for Switching to the SPT is available only on platform: Initially, a single PIM-SM tree called a shared tree to distribute traffic. It is called shared because all traffic for the group, regardless of the source, or the location of the source, must pass through the RP. The shared tree is unidirectional; that is, all multicast traffic flows only from the RP to the receivers. Once a receiver receives traffic from the RP, PM-SM switches to shortest path trees (SPT) to forward multicast traffic, which connects the receiver directly to the source. You can configure PIM to switch over to the SPT when the router receives multicast packets at or beyond a specified rate. IP Version IPv4 IPv6 Task Command Syntax Configure PIM to switch over to the SPT when the ip pim spt-threshold multicast packet rate is at or beyond a specified rate. The {value | infinity} keyword infinity directs PIM to never switch to the SPT. Default: 10 kbps Configure PIM to switch over to the SPT when the ip pim spt-threshold multicast packet rate is at or beyond a specified rate. The {value | infinity} keyword infinity directs PIM to never switch to the SPT. Default: 10 kbps Command Mode CONFIGURATION CONFIGURATION PIM-SM Graceful Restart e PIM-SM Graceful Restart is supported only on platform e PIM-SM Graceful Restart is supported only on platform x with FTOS 8.2.1.0 and later. When a PIM neighbor restarts and the liveliness timer for that neighbor expires, the join/prune states received from the neighbor expire, and the corresponding interfaces are removed from the outgoing list of multicast entries. The effect of this is that active multicast sessions are brought down. FTOS supports PIM-SM graceful restart based on the GenID. Per RFC 4601, hello messages should contain a Generation_Identifier option, which contains a randomly generated value (GenID) that is regenerated each time PIM forwarding is started or restarted on the interface, including when the router restarts. When a router receives from a neighbor a hello message with a new GenID, any old hello information about that neighbor should be discarded and superseded by the information from the new hello message. FTOS supports graceful restart based on the GenID. A Dell Force10 PIM router announces its graceful restart capability to its neighbors up front as an option in its hello messages. If a graceful-restart capable router recognizes that a graceful-restart capable neighbor has restarted, it preserves the state from the neighbor and continues forwarding multicast traffic while the neighbor restarts. 718 | PIM Sparse-Mode