Dropping hello messages without the Generation ID option
About dropping hello messages without the Generation ID option
A device generates a generation ID for hello messages when an interface is enabled with PIM. The generation ID is a random value, but it changes only when the status of the device changes. If a PIM device finds that the generation ID in a hello message from the upstream device has changed, it assumes that the status of the upstream device has changed. In this case, it sends a join message to the upstream device for status update. You can configure an interface to drop hello messages without the generation ID options to promptly know the status of an upstream device.
Procedure
Enter system view.
system-view
Enter interface view.
interface interface-type interface-number
Enable the interface to drop hello messages without the Generation ID option.
pim require-genid
By default, an interface accepts hello messages without the Generation ID option.