Maintaining PIM involves querying statistics about the outbound interfaces of IPv4 PIM SM entries, clearing PIM statistics, monitoring PIM running status, and locating faults through PIM debugging information.
You can determine whether the number of existing outbound interfaces in IPv4 PIM-SM entries exceeds the upper limit by checking statistics about outbound interfaces in IPv4 PIM-SM entries.
If PIM status information in IPv4 PIM routing entries of a downstream interface is unnecessary, delete them from the downstream interface. The deletion does not affect IGMP or static group join status information.
You can monitor the PIM running status by checking unicast routes, BSRs, and RPs used by PIM, statistics about PIM control messages, and information about PIM neighbors and the PIM routing table.