DHCP (Dynamic Host Configuration Protocol) is the system that automatically assigns IP addresses to every device on your network, so you do not have to configure each one by hand. This guide explains how it works and links to deep dives on each setting and error.
How DHCP works
When a device joins your network, it requests an address from the DHCP server (usually your router). The server leases an address for a set period - the DHCP lease time - from a pool defined by the DHCP range.
Key DHCP settings
- DHCP reservation - pin a fixed IP to a specific device.
- DHCP client ID - how devices identify themselves.
- DHCP client list - see what is connected.
- DHCP snooping - a security feature on managed networks.
Common DHCP errors and fixes
When DHCP misbehaves, devices cannot get online. The most common issues:
- DHCP error - general troubleshooting.
- DHCP not enabled.
- DHCP lookup failed (common on Chromebooks).
Related concepts
A few neighboring topics often come up alongside DHCP: Double NAT and the IP helper service. Understanding these rounds out your grasp of how addresses and traffic flow on your network.
