DHCPINFORMviestillä

DHCPINFORMviestillä, often shortened to DHCP INFORM, is a message type within the Dynamic Host Configuration Protocol (DHCP) used for obtaining specific configuration parameters without requesting a full IP address lease. Unlike a standard DHCPDISCOVER or DHCPREQUEST, a DHCPINFORM message is sent by a client that already possesses a valid IP address and subnet mask.

The primary purpose of a DHCPINFORM message is to allow a client to query the DHCP server for additional configuration options that are not necessarily tied to its IP address assignment. This can include information such as DNS server addresses, domain names, TFTP server details, or boot file names. The client sends this message when it needs to update its network configuration or obtain settings that were not provided during the initial IP address lease process.

When a DHCP server receives a DHCPINFORM message, it responds with a DHCPACK message that contains only the requested configuration options. The client does not receive a new IP address or have its existing lease modified by this transaction. This makes DHCPINFORM a lightweight and efficient mechanism for clients to retrieve necessary network settings without disrupting their current IP connectivity. It is particularly useful in scenarios where devices might have static IP addresses but still require dynamic updates of other network parameters.