ZyXEL ES-4124 User Guide - Page 267

DHCP Relay

Page 267 highlights

Chapter 33 DHCP The following table describes the labels in this screen. Table 102 IP Application > DHCP Server Status Detail LABEL DESCRIPTION Start IP Address This field displays the starting IP address of the IP address pool configured for this DHCP server instance. End IP Address This field displays the last IP address of the IP address pool configured for this DHCP server instance. Subnet Mask This field displays the subnet mask value sent to clients from this DHCP server instance. Default Gateway This field displays the default gateway value sent to clients from this DHCP server instance. Primary DNS Server This field displays the primary DNS server value sent to clients from this DHCP server instance. Secondary DNS This field displays the secondary DNS server value sent to clients from this DHCP Server server instance. Address Leases This section displays information about the IP addresses this DHCP server issued to clients. Index This field displays a sequential number for each DHCP request handled by the Switch. IP Address This is the IP address issued to a DHCP client. Timer This field displays the time remaining before the DHCP client has to renew its IP address. Hardware Address This field displays the MAC address of the DHCP client. It may also display SELF OCCUPIED ADDRESS, if the IP address cannot be used for DHCP because it is already assigned to the Switch itself. Hostname This field displays the system name of the client. 33.4 DHCP Relay Configure DHCP relay on the Switch if the DHCP clients and the DHCP server are not in the same broadcast domain. During the initial IP address leasing, the Switch helps to relay network information (such as the IP address and subnet mask) between a DHCP client and a DHCP server. Once the DHCP client obtains an IP address and can connect to the network, network information renewal is done between the DHCP client and the DHCP server without the help of the Switch. The Switch can be configured as a global DHCP relay. This means that the Switch forwards all DHCP requests from all domains to the same DHCP server. You can also configure the Switch to relay DHCP information based on the VLAN membership of the DHCP clients. 33.4.1 DHCP Relay Agent Information The Switch can add information about the source of client DHCP requests that it relays to a DHCP server by adding Relay Agent Information. This helps provide authentication about the source of the requests. The DHCP server can then provide an IP address based on this information. Please refer to RFC 3046 for more details. ES-4124 User's Guide 267

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Chapter 33 DHCP
ES-4124 User’s Guide
267
The following table describes the labels in this screen.
33.4
DHCP Relay
Configure DHCP relay on the Switch if the DHCP clients and the DHCP server are not in the
same broadcast domain. During the initial IP address leasing, the Switch helps to relay
network information (such as the IP address and subnet mask) between a DHCP client and a
DHCP server. Once the DHCP client obtains an IP address and can connect to the network,
network information renewal is done between the DHCP client and the DHCP server without
the help of the Switch.
The Switch can be configured as a global DHCP relay. This means that the Switch forwards all
DHCP requests from all domains to the same DHCP server. You can also configure the Switch
to relay DHCP information based on the VLAN membership of the DHCP clients.
33.4.1
DHCP Relay Agent Information
The Switch can add information about the source of client DHCP requests that it relays to a
DHCP server by adding
Relay Agent Information
. This helps provide authentication about
the source of the requests. The DHCP server can then provide an IP address based on this
information. Please refer to RFC 3046 for more details.
Table 102
IP Application > DHCP Server Status Detail
LABEL
DESCRIPTION
Start IP Address
This field displays the starting IP address of the IP address pool configured for this
DHCP server instance.
End IP Address
This field displays the last IP address of the IP address pool configured for this
DHCP server instance.
Subnet Mask
This field displays the subnet mask value sent to clients from this DHCP server
instance.
Default Gateway
This field displays the default gateway value sent to clients from this DHCP server
instance.
Primary DNS
Server
This field displays the primary DNS server value sent to clients from this DHCP
server instance.
Secondary DNS
Server
This field displays the secondary DNS server value sent to clients from this DHCP
server instance.
Address Leases
This section displays information about the IP addresses this DHCP server issued
to clients.
Index
This field displays a sequential number for each DHCP request handled by the
Switch.
IP Address
This is the IP address issued to a DHCP client.
Timer
This field displays the time remaining before the DHCP client has to renew its IP
address.
Hardware
Address
This field displays the MAC address of the DHCP client.
It may also display
SELF OCCUPIED ADDRESS
, if the IP address cannot be used
for DHCP because it is already assigned to the Switch itself.
Hostname
This field displays the system name of the client.