Huawei DR814Q - Manual (Page 86)

User Manual
Aolynk DR814Q ADSL2+ Broadband Router
6 Troubleshooting
81
9) The DNS server IP address specified on the PC is correct. If you specify the PC to
obtain the DNS server address dynamically, verify with your ISP that the address
configured on the DR814Q is correct, and then you can use the ping utility to test
the connectivity with your ISP’s DNS server.
10) Generally, if a host can ping the Internet IP address, but cannot open the Web
pages, the DNS server of the ISP is experiencing a failure temporarily. In this case,
you can choose either of the following to solve the problem: Manually change your
PC’s DNS IP address to the address of a normally functioning DNS server. Log
into the Web page of the DR814Q and manually modify the configuration for DNS
Relay (refer to section 4.2.2 “DNS Relay"), and then check by the nslookup
command as instructed in section 6.2.2 “Nslookup”.
Symptom 8: Fail to save the changes made on the Web configuration pages.
Solution: Make sure that you click <Apply> to confirm every change you have made.
After completing all the settings, enter the [Save Configuration] page to save them, thus
making them take effect when the DR814Q is powered on next time.
Symptom 9: You can access most of the websites, but sometimes connection to some
websites times out. When you set the DR814Q to operate in the bridge mode and your
PC to establish a dialup connection, you can access the websites normally. How does
this problem come?
Solution: This problem is due to the MTU value from the client to the DR814Q. It is set
too large. To solve the problem, enter the specific editing page (refer to section 4.2.1
“WAN”) to change the MTU value to a smaller one, such as 1440, and then select true
from the [TCP MSS Clamp] drop-down list.
In addition, if you fail to send an E-mail in the LAN, but succeed when you change an
SMTP server, or you fail to transfer files by the point-to-point communication software,
but succeed in transferring photos with other friends, this may be caused by the
settings of the MTU for the LAN interface if you are sure the server functions well. Enter
the [LAN Connections] tab page (refer to section 4.3.1 “LAN”) to change the MTU value
to a smaller one, such as 1440, and then select true from the [TCP MSS Clamp]
drop-down list.
Symptom 10: Some services are unavailable once the firewall is enabled.
Solution: As the firewall rules of the DR814Q are very strict, it is recommended
someone familiar with the WAN services and router configuration enable the firewall
and configure the firewall rules. Before the creation of firewall rules, you must be clear
about the Internet service deployment. It is recommended that you disable the firewall.