TP-LINK TD-8817 User Manual

Page of 58
TD-8817
ADSL2/2+ Ethernet/USB Router User Guide 
 
 
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expired, the user will be automatically assigned a new dynamic IP address. The default 
is 259200 seconds. 
• 
DNS Relay: If you want to disable this feature, you just need to set both Primary and 
secondary DNS IP to 0.0.0.0. If you want to use DNS relay, you can setup DNS server IP 
to 192.168.1.1 on their Computer. If not, the device will perform as no DNS relay. 
• 
Primary DNS Server: Type in your preferred DNS server. 
• 
Secondary DNS Server: Type in your preferred DNS server. 
• 
Current Pool Summary: Click the button, you can view the IP addresses that the DHCP 
Server gives out. 
) 
Note: 
If Use Auto Discovered DNS Server Only is selected in DNS Relay, this router will accept the 
first received DNS assignment from one of the PPPoA, PPPoE or MER/DHCP enabled PVC(s) 
during the connection establishment. If Use User Discovered DNS Server Only is selected in 
DNS Relay, it is necessary for you to enter the primary and optional secondary DNS server IP 
addresses. After type in the address, click SAVE button to save it and invoke it.   
¾  DHCP Relay: Select Relay, then you will see the next screen (shown in Figure 4-11), the 
Router will work as a DHCP Relay. A DHCP relay is a computer that forwards DHCP data 
between computers that request IP addresses and the DHCP server that assigns the 
addresses. Each of the device's interfaces can be configured as a DHCP relay. If it is enabled, 
the DHCP requests from local PCs will forward to the DHCP server runs on WAN side. To 
have this function working properly, please run on router mode only, disable the DHCP server 
on the LAN port, and make sure the routing table has the correct routing entry. 
 
Figure 4-11 
• 
DHCP Server IP for Relay Agent: Enter the DHCP server IP Address runs on WAN 
side. 
) 
Note: 
If you select Disabled, the DHCP function will not take effect.