Solaris DHCP Administration Guide

How Solaris DHCP Client Manages Network Configuration Information

After the information packet is obtained from a DHCP server, dhcpagent configures the network interface and brings it up, controlling the interface for the duration of the lease time for the IP address. The dhcpagent daemon maintains the configuration data in an internal table held in memory. The system startup scripts use the dhcpinfo command to extract configuration option values from the dhcpagent daemon's table. The values are used to configure the system and enable it to join the network.

The agent waits passively until a period of time elapses, usually half the lease time, and then requests an extension of the lease from a DHCP server. If the dhcpagent daemon finds that the interface is down or the IP address has changed, it does not control the interface until it is instructed by the ifconfig command to do so. If the dhcpagent daemon finds that the interface is up and the IP address hasn't changed, it sends a request to the server for a lease renewal. If the lease cannot be renewed, the dhcpagent daemon takes down the interface at the end of the lease time.