User's Manual

B222s User’s Guide 79
CHAPTER 8
DNS Route
8.1 Overview
DNS ( Dom ain Nam e System ) is for m apping a dom ain nam e t o its corresponding I P address and
vice versa. The DNS server is ext rem ely im port ant because wit hout it , you m ust know the I P
address of a m achine befor e you can access it.
I n addition t o t he system DNS server( s) , each WAN interface ( service) is set to have it s own stat ic
or dynam ic DNS server list. You can configure a DNS stat ic rout e t o forward DNS queries for cert ain
dom ain nam es t hrough a specific WAN int erface t o its DNS server( s). The LTE Device uses a system
DNS server (in t he order you specify in t he Broa dband screen) t o resolve dom ain nam es t hat do
not m atch any DNS rout ing ent ry. Aft er t he LTE Device receives a DNS reply from a DNS ser ver, it
creat es a new ent ry for t he resolved I P address in t he routing table.
I n t he following exam ple, t he DNS server 168.92.5.1 obt ained from t he WAN interface atm 0.100 is
set t o be t he system DNS server. The DNS server 10.10.23.7 is obt ained from t he WAN int erface
ppp1.123. You configure a DNS rout e for * exam ple.com t o have t he LTE Device forward DNS
request s for t he dom ain nam e m ail.exam ple.com t hrough the WAN int erface ppp1.123 t o t he DNS
server 10.10.23.7.
Figure 43 Exam ple of DNS Rout ing Topology
8.1.1 What You Can Do in this Chapter
The DN S Rou t e screens let you view and configure DNS rout es on the LTE Device (
Section 8.2 on
page 80) .
WAN
LAN
atm 0.100
ppp1.123
DNS: 10.10.23.7
DNS: 168.92.5.1
sip.service.com
m ail.ex am ple.com
( Default )