A wastewater plant has receiver VLANs with no multicast router attached, yet access switches still need periodic membership queries to refresh IGMP snooping state. Which role should be enabled on a switch in each such VLAN?
Select an answer to reveal the explanation.
Short Explanation
Snooping only works if something keeps asking “who still wants this channel?” Normally the multicast router sends those queries. When no router sits on the VLAN, an IGMP querier on a switch fills that job so membership state does not time out into a flood.
Full Explanation
IGMP queriers periodically send General Queries so hosts refresh membership and snooping tables remain accurate. On a Layer-2-only segment without a multicast router, enabling an IGMP querier on a switch provides that query function. Without it, snooping entries expire and many platforms revert toward flooding, undermining the original multicast containment goal.