HP 6125G HP 6125G & 6125G/XG Blade Switches IP Multicast Configuration - Page 143

Step Command Remarks 4. Configure PIM neighbor timeout time. Optional. pim hello-option holdtime interval 105 seconds by default. 5. Configure the prune message Optional. delay time (LAN-delay). pim hello-option lan-delay interval 500 milliseconds by default. 6. Configure the prune override pim hello-option override-interval Optional. interval. interval 2,00 milliseconds by default. 7. Disable join suppression. pim hello-option neighbor-tracking Enabled by default. 8. Configure the interface to reject hello messages without pim require-genid a generation ID. By default, hello messages without Generation_ID are accepted. Configuring the prune delay Configuring a prune delay interval on an upstream router on a shared network segment can make the upstream router not perform the prune action immediately after it receives the prune message from its downstream router. Instead, the upstream router maintains the current forwarding state for a period of time that the prune delay interval defines. In this period, if the upstream router receives a join message from the downstream router, it cancels the prune action. Otherwise, it performs the prune action. To configure the prune delay time: Step 1. Enter system view. 2. Enter PIM view. 3. Configure the prune delay interval. Command system-view pim prune delay interval Remarks N/A N/A Optional. By default, the prune delay is not configured. Configuring PIM common timers PIM routers discover PIM neighbors and maintain PIM neighboring relationships with other routers by periodically sending out hello messages. After receiving a hello message, a PIM router waits a random period, which is smaller than the maximum delay between hello messages, before sending a hello message. This delay avoids collisions that occur when multiple PIM routers send hello messages simultaneously. A PIM router periodically sends join/prune messages to its upstream for state update. A join/prune message contains the join/prune timeout time. The upstream router sets a join/prune timeout timer for each pruned downstream interface. Any router that has lost assert election will prune its downstream interface and maintain the assert state for a period of time. When the assert state times out, the assert losers will resume multicast forwarding. When a router fails to receive subsequent multicast data from multicast source S, the router does not immediately delete the corresponding (S, G) entry. Instead, it maintains the (S, G) entry for a period of time (namely, the multicast source lifetime) before deleting the (S, G) entry. 132