What are the pros and cons of global and interface DHCP?

Port-based DHCP and global DHCP are two modes of DHCP server operation, they play different roles in network configuration and management, there is no one better, only the one more suitable.

Global DHCP-based: In this mode, the DHCP server configuration is applied to the entire network, providing a centralized management approach. With a single configuration file, the DHCP server can control all network interfaces. In global mode, the DHCP server listens for all incoming DHCP requests and attempts to provide an IP address for each request. For example, IP addresses and DNS server addresses can be dynamically assigned to two in-office terminals in an organization.

Port-based DHCP: Unlike global mode, port-based DHCP mode restricts the configuration of the DHCP server to specific network interfaces or ports. This means that each port may have its own individual IP address pool and configuration. This mode is suitable for scenarios where a separate IP address range is required for a specific subnet or group of devices.