24-Port Layer 3 Switch Management Guide

D YNAMIC H OST C ONFIGURATION P ROTOCOL
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Dynamic Host Configuration Protocol
Dynamic Host Configuration Protocol (DHCP) can dynamically allocate
an IP address and other configuration information to network clients
when they boot up. If a subnet does not already include a BOOTP or
DHCP server, you can relay DHCP client requests to a DHCP server on
another subnet, or configure the DHCP server on this switch to support
that subnet.
When configuring the DHCP server on this switch, you can configure an
address pool for each unique IP interface, or manually assign a static IP
address to clients based on their hardware address or client identifier. The
DHCP server can provide the host’s IP address, domain name, gateway
router and DNS server, information about the host’s boot image including
the TFTP server to access for download and the name of the boot file, or
boot information for NetBIOS Windows Internet Naming Service
(WINS).
Configuring DHCP Relay Service
This switch supports
DHCP relay service for
attached host devices.
If DHCP relay is
enabled, and this
switch sees a DHCP
request broadcast, it
inserts its own IP
address into the request so that the DHCP server will know the subnet
where the client is located. Then, the switch forwards the packet to the
DHCP server. When the server receives the DHCP request, it allocates a
free IP address for the DHCP client from its defined scope for the DHCP
client’s subnet, and sends a DHCP response back to the DHCP relay agent
(i.e., this switch). This switch then broadcasts the DHCP response received
from the server to the client.
Provides IP address
compatible with switch
segment to which client
is attached
DHCP
Server