Configuring Dhcp Relay And Option 82 Information - Edge-Core ES4528V-38 Management Manual

| Configuring the Switch
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HAPTER

Configuring DHCP Relay and Option 82 Information

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ONFIGURING
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EB NTERFACE
To configure UPnP:
Click Configuration, UPnP.
1.
Enable or disable UPnP, then set the TTL and advertisement values.
2.
Click Save.
3.
Figure 40: UPnP Configuration
O
ELAY AND PTION
The switch supports DHCP relay service for attached host devices. If a
subnet does not include a DHCP server, you can relay DHCP client requests
to a DHCP server on another subnet.
When DHCP relay is enabled and the switch sees a DHCP request
broadcast, it inserts its own IP address into the request (so that the DHCP
server knows the subnet of the client), then 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 switch. The switch
then broadcasts the DHCP response to the client.
DHCP also provides a mechanism for sending information about the switch
and its DHCP clients to the DHCP server. Known as DHCP Option 82, it
allows compatible DHCP servers to use the information when assigning IP
addresses, or to set other services or policies for clients.
Using DHCP Relay Option 82, clients can be identified by the VLAN and
switch port to which they are connected rather than just their MAC
address. DHCP client-server exchange messages are then forwarded
directly between the server and client without having to flood them to the
entire VLAN.
In some cases, the switch may receive DHCP packets from a client that
already includes DHCP Option 82 information. The switch can be configured
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NFORMATION