Dell MX9116n EMC SmartFabric OS10 User Guide - Page 181

DHCP Option Description DHCP relay agent 82 - Helps secure DHCP traffic that goes through a DHCP relay agent, and ensures that communication information option between the DHCP relay agent and the DHCP server is not compromised. User port stacking 230 - Stacking option variable that provides the DHCP server stack-port details when the DHCP offer is set End 255 - Signal of the last option in the DHCP packet DHCP server The Dynamic Host Configuration Protocol (DHCP) server provides network configuration parameters to DHCP clients on request. A DHCP server dynamically allocates four required IP parameters to each computer on the virtual local area network (VLAN) - the IP address, network mask, default gateway, and name server address. DHCP IP address allocation works on a client/server model where the server assigns the client reusable IP information from an address pool. DHCP automates network-parameter assignment to network devices. Even in small networks, DHCP makes it easier to add new devices to the network. The DHCP access service provides a centralized, server-based setup to add clients to the network. This setup means you do not have to manually create and maintain IP address assignments for clients. When you use DHCP to manage a pool or IP addresses among hosts, you reduce the number of IP addresses you need. DHCP manages the IP address pool by leasing an IP address to a host for a limited period, allowing the DHCP server to share a limited number of IP addresses. DHCP also provides a central database of devices that connects to the network and eliminates duplicate resource assignments. Automatic address allocation Automatic address allocation is an address assignment method that the DHCP server uses to lease an IP address to a client from a pool of available addresses. You cannot configure an empty DHCP pool under a DHCP pool configuration. For a successful commit, you must have either a network statement or host/hardware-address (manual binding) configuration. An IP address pool is a range of addresses that the DHCP server assigns. The subnet number indexes the address pools. 1. Enable DHCP server-assigned dynamic addresses on an interface in DHCP mode. ip dhcp server 2. Create an IP address pool and provide a name in DHCP mode. pool name 3. Enter the subnet from which the DHCP server may assign addresses in DHCP mode. The network option specifies the subnet address. The prefix-length option specifies the number of bits used for the network portion of the address, from 18 to 31. network network/prefix-length 4. Enter a range of IP addresses from the subnet specified above, which the DHCP server uses to assign addresses in DHCP mode. range {ip-address1 [ip-address2]} NOTE: Configure at least one interface to match one of the configured network pools. An interface matches a network pool when its IP address is included in the subnet defined for that network pool. For example, an interface with IP address 10.1.1.1/24 matches a pool configured with network 10.1.1.0/24. DHCP server automatic address allocation OS10(config)# ip dhcp server OS10(config-dhcp)# pool Dell OS10(config-dhcp-Dell)# default-router 20.1.1.1 OS10(config-dhcp-Dell)# network 20.1.1.0/24 OS10(config-dhcp-Dell)# range 20.1.1.2 20.1.1.8 Show running configuration OS10(conf-dhcp-Dell)# do show running-configuration ... ! System management 181