Cisco Certified Support Technician (CCST) NetworkingIP ServicesMedium
A network technician is troubleshooting an intermittent network connectivity issue where some devices periodically lose their IP addresses. Upon investigation, they discover that the DHCP server is configured with a very short lease time (e.g., 5 minutes) for a large subnet with many clients, leading to excessive DHCP renewal traffic. Which of the following is a direct consequence of an overly short DHCP lease time in a busy network?
- AHigher broadcast traffic and increased load on the DHCP server.
- BReduced network bandwidth utilization due to fewer DHCP requests.
- CFaster IP address release and reuse, improving IP address availability.
- DIncreased DNS resolution failures due to stale IP addresses.
Show answer & explanationAnswer & explanation
Correct answer: A. Higher broadcast traffic and increased load on the DHCP server.
A very short DHCP lease time in a busy network forces clients to frequently renew their IP addresses, leading to a significant increase in DHCP-related broadcast traffic and a higher processing load on the DHCP server.
Why the other options are wrong
- B. Short lease times increase, not reduce, DHCP-related network traffic due to frequent renewals.
- C. While it allows faster reuse, the negative impact of increased traffic and server load outweighs this benefit in a busy network scenario.
- D. Stale IP addresses are more likely with long lease times and unreleased IPs, not short ones.
Short DHCP Lease Consequence
An overly short DHCP lease time in a busy network leads to excessive DHCP renewal traffic and increased load on the DHCP server.
- Clients renew more frequently.
- Generates more broadcast traffic.
- Increases DHCP server CPU and memory usage.
Memory trick: Short lease, high demand: everyone's always asking for a new car.