Evidence Cross-8/HPoE-10G, Руководство пользователя

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10-2 Relay
10-2.1 Configuration
A DHCP relay agent is used to forward and to transfer DHCP messages
between the clients and the server when they are not in the same subnet
domain. It stores the incoming interface IP address in the GIADDR field of the
DHCP packet. The DHCP server can use the value of GIADDR field to
determine the assigned subnet. For such condition, please make sure the
switch configuration of VLAN interface IP address and PVID(Port VLAN ID)
correctly.
Web Interface
To configure DHCP Relay in the web interface:
1.
Click DHCP, Relay and Configuration.
2. Specify the Relay Mode, Relay server, Relay Information Mode, Relay Information Policy.
3. Click Apply.
Figure 10-2.1: The DHCP Relay Configuration
Parameter description:

Relay Mode :
Indicates the DHCP relay mode operation.
Possible modes are:
on: Enable DHCP relay mode operation. When DHCP relay mode operation is enabled, the
agent forwards and transfers DHCP messages between the clients and the server when
they are not in the same subnet domain. And the DHCP broadcast message won't be
flooded for security considerations.
off: Disable DHCP relay mode operation.

Relay Server :
Indicates the DHCP relay server IP address.

Relay Information Mode :
Indicates the DHCP relay information mode option operation. The option 82 circuit ID
format as "[vlan_id][module_id][port_no]". The first four characters represent the VLAN ID,
the fifth and sixth characters are the module ID(in standalone device it always equal 0, in
stackable device it means switch ID), and the last two characters are the port number. For