IP Services
261
Instruction Manual - NXA-ENET8-POE+
By default, DHCP option 66/67 parameters are not carried in a DHCP server reply. To ask for a DHCP reply with option 66/
67 information, the DHCP client request sent by this switch includes a
parameter request list
asking for this information.
Besides, the client request also includes a
vendor class identifier
that allows the DHCP server to identify the device, and
select the appropriate configuration file for download. This information is included in Option 55 and 124.
The server should reply with the TFTP server name and boot file name.
Note that the vendor class identifier can be formatted in either text or hexadecimal, but the format used by both the client
and server must be the same.
The following table lists the options on this page:
Perform these steps to configure a DHCP client identifier:
1.
Click
IP Service
>
DHCP
>
Client
.
2.
Mark the check box to enable this feature. Select the default setting, or the format for a vendor class identifier. If a non-default
value is used, enter a text string or hexadecimal value.
3.
Click
Apply
.
Configuring DHCP Relay Service
Use the IP Service > DHCP > Relay page to configure DHCP relay service for attached host devices, including DHCP option 82
information. DHCP provides an option for sending information about its DHCP clients to the DHCP server (specifically, the interface
on the relay server through which the DHCP client request was received). Also known as DHCP Relay Option 82, it allows compatible
DHCP servers to use this information when assigning IP addresses, or to set other services or policies for clients.
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 passes the DHCP response
received from the server to the client.
Options 55 and 124 Statements
Option
Keyword
Statement Parameter
55
dhcp-parameter-request-list a list of parameters,
separated by ','
124
vendor-class-identifier
a string indicating the
vendor class identifier
IP Service - DHCP (Client) Options
VLAN
ID of configured VLAN
Vendor Class ID
The following options are supported when the check box is marked to enable this feature:
• Default - The default string is the model number.
• Text - A text string (Range: 1-32 characters)
• Hex - A hexadecimal value (Range: 1-64 characters)
FIG. 315
Specifying a DHCP Client Identifier