D-Link DES-3526 - Switch - Stackable Manual - Dhcp/bootp Relay
DES-3526 / DES-3526DC Fast Ethernet Layer 2 Switch
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DHCP/BOOTP Relay
The relay hops count limit allows the maximum number of hops (routers) that the DHCP/BOOTP
messages can be relayed through to be set. If a packet’s hop count is more than the hop count limit, the
packet is dropped. The range is between 1 and 16 hops, with a default value of 4. The relay time
threshold sets the minimum time (in seconds) that the Switch will wait before forwarding a
BOOTREQUEST packet. If the value in the seconds field of the packet is less than the relay time
threshold, the packet will be dropped. The range is between 0 and 65,536 seconds, with a default value
of 0 seconds.
DHCP / BOOTP Relay Global Settings
To enable and configure DHCP/BOOTP Relay Global Settings on the Switch, click Configuration
> Layer 3 Networking > DHCP/BOOTP Relay > DHCP/BOOTP Relay Global Settings:
Figure 6- 86. DHCP/ BOOTP Relay Global Settings window
The following fields can be set:
Parameter
Description
Relay State
This field can be toggled between Enabled and Disabled using the pull-down menu.
It is used to enable or disable the DHCP/BOOTP Relay service on the Switch. The
default is Disabled
Relay Hops Count
Limit (1-16)
This field allows an entry between 1 and 16 to define the maximum number of router
hops DHCP/BOOTP messages can be forwarded across. The default hop count is 4.
Relay Time Threshold
(0-65535)
Allows an entry between 0 and 65535 seconds, and defines the maximum time limit
for routing a DHCP/BOOTP packet. If a value of 0 is entered, the Switch will not
process the value in the seconds field of the BOOTP or DHCP packet. If a non-zero
value is entered, the Switch will use that value, along with the hop count to determine
whether to forward a given BOOTP or DHCP packet.
DHCP Agent
Information Option 82
State
This field can be toggled between Enabled and Disabled using the pull-down menu.
It is used to enable or disable the DHCP Agent Information Option 82 on the Switch.
The default is Disabled.
Enabled –When this field is toggled to Enabled the relay agent will insert and remove
DHCP relay information (option 82 field) in messages between DHCP servers and
clients. When the relay agent receives the DHCP request, it adds the option 82
information, and the IP address of the relay agent (if the relay agent is configured), to