This read-only Counter64 counts queries discarded because the ingress port was in a blocking state (for example, held down by spanning tree or an access-control action) when the query arrived. This ties multicast query loss directly to L2 loop-prevention or security state on the port, useful when troubleshooting why an IPTV stream briefly drops during a topology change; because it is drawn from the most recently completed 24-hour bin, frozen once the day rolled over, it is frozen and safe to use for day-over-day comparison, since no further traffic will ever be added to it. On a residential VLAN used for multicast video delivery, a count of 543 over the last completed collection window is the kind of number an admin would trend against the join/leave rate on the same port to judge whether it's normal channel-surfing or an anomaly worth a closer look.