ZyXEL Communications IES-1248-51A, User Manual

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Chapter 28 DHCP Relay
IES-1248-51V User’s Guide
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The following table describes the labels in this screen.
Table 61 DHCP Relay
LABEL DESCRIPTION
VLAN ID Enter the ID of the VLAN served by the specified DHCP relay(s). Enter
0 to set up the default DHCP relay(s).
Enable DHCP
Relay: Select this to have the IES-1248-51V relay DHCP requests in the
selected VLAN to a DHCP server and the server’s responses back to
the clients.
Enable Option82
Sub-option1
(Circuit ID) Select this to have the IES-1248-51V add the originating port
numbers to DHCP requests in the selected VLAN regardless of
whether the DHCP relay is on or off. In the field next to the check box,
you can also specify up to 23 ASCII characters of additional
information for the IES-1248-51V to add to the DHCP requests that it
relays to a DHCP server. Examples of information you could add would
be the chassis number of the IES-1248-51V or the ISP’s name.
Enable Option82
Sub-option2
(Remote ID) Enable DHCP relay info to have the IES-1248-51V add the sub-option
2 (Remote ID) to DHCP requests in the selected VLAN regardless of
whether the DHCP relay is on or off. In the field next to the check box,
you can also specify up to 23 ASCII characters of additional
information for the IES-1248-51V to add to the DHCP requests that it
relays to a DHCP server.
Primary Server IP Enter the IP address of one DHCP server to which the switch should
relay DHCP requests for the selected VLAN.
Secondary Server
IP Enter the IP address of a second DHCP server to which the switch
should relay DHCP requests for the selected VLAN. Enter 0.0.0.0 if
there is only one DHCP relay for the selected VLAN.
Relay Mode Specify how the IES-1248-51V relays DHCP requests for the selected
VLAN.
Auto - The IES-1248-51V routes DHCP requests to the active server
for the VLAN.
Both - The IES-1248-51V routes DHCP requests to the primary and
secondary server for the VLAN, regardless of which one is active.
Option Mode Specify the DHCP option 82 format, either private or TR-101 format.
See
Section 28.2 on page 217 for more information.
Active Server This field has no effect if the Relay Mode is Both. If the Relay Mode
is Auto, select which DHCP server (the primary one or the secondary
one) to which the IES-1248-51V should relay DHCP requests for the
selected VLAN.
Apply Click Apply to save your changes to the IES-1248-51V’s volatile
memory. The IES-1248-51V loses these changes if it is turned off or
loses power, so use the Config Save link on the navigation panel to
save your changes to the non-volatile memory when you are done
configuring.
Cancel Click Cancel to begin configuring this screen afresh.
Server List This section lists the current DHCP relay settings for each VLAN. An
asterisk in parentheses (*) indicates which DHCP server is active for
each VLAN.
VID This field displays the ID of the VLAN served by the specified DHCP
relay(s).