Bandwidth Management and PIM Graceful Restart
When using PIM graceful restart, after the routing process restarts on the Routing Engine, previously admitted interfaces are always readmitted and the available bandwidth is adjusted on the interfaces. When using the adaptive bandwidth option, the bandwidth measurement is initially based on the configured or default starting bandwidth, which might be inaccurate during the first minute. This means that new flows might be incorrectly rejected or admitted temporarily. You can correct this problem by issuing the clear multicast bandwidth-admission operational command.
If PIM graceful restart is not configured, after the routing process restarts, previously admitted or rejected interfaces might be rejected or admitted in an unpredictable manner.
