Blade ICE G8124-E Personal Computer User Manual


 
BLADEOS 6.5.2 Application Guide
BMD00220, October 2010 Chapter 15: Basic IP Routing 227
Dynamic Host Configuration Protocol
Dynamic Host Configuration Protocol (DHCP) is a transport protocol that provides a framework for
automatically assigning IP addresses and configuration information to other IP hosts or clients in a
large TCP/IP network. Without DHCP, the IP address must be entered manually for each network
device. DHCP allows a network administrator to distribute IP addresses from a central point and
automatically send a new IP address when a device is connected to a different place in the network.
The switch accepts gateway configuration parameters if they have not been configured manually.
The switch ignores DHCP gateway parameters if the gateway is configured.
DHCP is an extension of another network IP management protocol, Bootstrap Protocol (BOOTP),
with an additional capability of being able to allocate reusable network addresses and configuration
parameters for client operation.
Built on the client/server model, DHCP allows hosts or clients on an IP network to obtain their
configurations from a DHCP server, thereby reducing network administration. The most significant
configuration the client receives from the server is its required IP address; (other optional
parameters include the “generic” file name to be booted, the address of the default gateway, and so
forth).
To enable DHCP on a switch management interface, use the following command:
To configure DHCP operation on data interfaces, use the following command:
DHCP Relay Agent
DHCP is described in RFC 2131, and the DHCP relay agent supported on the G8124 is described in
RFC 1542. DHCP uses UDP as its transport protocol. The client sends messages to the server on
port 67 and the server sends messages to the client on port 68.
DHCP defines the methods through which clients can be assigned an IP address for a finite lease
period and allowing reassignment of the IP address to another client later. Additionally, DHCP
provides the mechanism for a client to gather other IP configuration parameters it needs to operate
in the TCP/IP network.
In the DHCP environment, the G8124 acts as a relay agent. The DHCP relay feature enables the
switch to forward a client request for an IP address to two BOOTP servers with IP addresses that
have been configured on the switch.
RS G8124(config)# system dhcp mgta
RS G8124(config)# system bootp