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ANUAL
2011, VALUEPOINT NETWORKS, INC. ALL RIGHTS RESERVED
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then the Controller relays this request to the default gateway. Finally, this request
is forwarded by the default gateway to the DNS server on the Internet. The DNS
reply issued by the DNS server is transmitted back to the client computer following
a reverse path. When the client computer receives the DNS reply, it knows the IP
address of the correspondent host and sends further packets to this IP address.
As illustrated above, the communication path could be broken at several stages.
The various OS provided network diagnostic tools, such as ping.exe or tracert.exe,
can be employed to find out TCP/IP-related communication problems.
Note: If two NICs are installed and operating on a client computer, TCP/IP may not work
properly due to incorrect entries in the routing table. Use the Windows Device Manager to
disable unnecessary NICs. The most common configuration that causes this problem is
when the Ethernet and WiFi LAN Cards are both enabled on a laptop at the same time.
4 . 1 .
T C P / I P
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E T T I N G S
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R O B L E M S
If the client is associated, check for client TCP/IP problems
The Controller does not respond to ping from the client computer.
o
Disable any unused NICs on the client computer.
o
Is Wireless Client or Layer-two isolation enabled on the Controller, or
an intervening AP?
Disable Isolation features to access local APs or other hardware
on the LAN.
o
Check whether the IP address of the client computer and the IP
address of the AP are in the same IP subnet.
Turn on Auto-IP to allow clients with invalid static IP Addresses
to connect.
Enable DHCP on the Controller and client.
The DNS server(s) do not respond to ping from the client computer.
o
Verify that the Controller WAN port is connected to the ISP by
checking the System LED, or checking the Status page in the
Controller Web GUI.
