Cisco Certified Network Professional Practice Test 2026 – Your All-in-One Guide to Exam Success!

Enabling DHCP snooping on a switch is a security feature designed to prevent rogue DHCP servers from handing out IP addresses to clients, ensuring that only authorized DHCP servers can provide IP configuration information. When DHCP snooping is activated, the switch begins to monitor DHCP messages and can take specific actions based on the configuration set by the network administrator.

If DHCP snooping is enabled after hours, the immediate effect is that the switch will begin monitoring DHCP traffic. If a DHCP request is received on an unauthorized port, it may result in that port being temporarily disabled to prevent any potential unauthorized DHCP offers from being sent out. This is often configured with a default duration, such as 30 seconds, after which the switch port is re-enabled, allowing for normal operations to resume if no further unauthorized activity is detected.

This action doesn't lock all user ports indiscriminately, nor does it directly prevent unauthorized access outright without further configuration. Allowing immediate DHCP requests would contradict the purpose of the feature, as it is meant to control and filter DHCP communications rather than simply permit them without scrutiny.