Prerequisites
Prerequisites
Before you configure the Cisco IOS DHCP Server feature, complete the following tasks:
•Identify an external File Transport Protocol (FTP), Trivial File Transfer Protocol (TFTP), or remote copy protocol (rcp) server that you will use to store the DHCP bindings database.
•Identify the IP addresses that you will enable the DHCP server to assign, and the IP addresses that you will exclude.
•Identify DHCP options for devices where necessary, including:
— Default boot image name
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—Default router(s)
—Domain Name System (DNS) server(s)
—NetBIOS name server
Decide on a NetBIOS node type (b, p, m, or h).
Decide on a DNS domain name.
DHCP Configuration Task List
The DHCP server database is organized as a tree. The root of the tree is the address pool for natural networks, branches are subnetwork address pools, and leaves are manual bindings to clients. Subnetworks inherit network parameters and clients inherit subnetwork parameters. Therefore, common parameters, for example the domain name, should be configured at the highest (network or subnetwork) level of the tree.
Note Inherited parameters can be overridden. For example, if a parameter is defined in both the natural network and a subnetwork, the definition of the subnetwork is used.
Address leases are not inherited. If a lease is not specified for an IP address, by default, the DHCP server assigns a
To configure the Cisco IOS DHCP Server feature, first configure a database agent or disable conflict logging, then configure IP addresses that the DHCP server should not assign (excluded addresses) and should assign (a pool of available IP addresses) to requesting clients. These configuration tasks are explained in the following sections. Each task in the following list is identified as required or optional.
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Configuring a DHCP Database Agent or Disabling DHCP Conflict Logging (Required)
Excluding IP Addresses (Required)
Configuring a DHCP Address Pool (Required)
Configuring Manual Bindings (Optional)
Configuring a DHCP Server Boot File (Optional)
Configuring the Number of Ping Packets (Optional)
Configuring the Timeout Value for Ping Packets (Optional)
Enabling the Cisco IOS DHCP Server Feature (Optional)
4Release 12.0(1)T
