Lantronix UBox UBX4100 - Manual (Page 54)

Troubleshooting
Troubleshooting: Network Issues
Communication Between your PC and the UBox
If you have determined via the status LEDs that the UBox is communicating with a
specific network, but network communication between the computer and the UBox is
not established, you can ping the UBox from the PC trying to communicate with the
UBox:
To ping the UBox:
1. From the Windows Start menu, select Run, type cmd, and click OK.
A command window opens.
2. At the prompt, type ping xxx.xxx.xxx.xxx (where xxx.xxx.xxx.xxx is the
IP address of the UBox). If the UBox replies, the physical and logical (IP subnet)
network communications are good. Proceed to step 4.
3. If you do not receive a reply from the ping, the problem is network related. Make
sure:
‹ IP addresses of the PC and UBox are on different subnets
‹ Physical network connections of the PC and UBox are established:
− Check network cable connections.
− Verify that switches/hubs are powered up.
− Verify that you have a network link light on the PC and UBox.
Note: Some Ethernet hubs/switches may not properly route UDP and
TCP traffic when connected to other hubs and switches. This is
especially true when your UBox is using Zeroconfig to obtain an IP
address. To avoid these issues, connect your UBox and your computer
to the same Ethernet hub/switch.
4. If you can ping the UBox, but the UBox software cannot establish a connection,
the UDP/TCP port is not correct or is blocked by a firewall. Temporarily disable
the firewall and see if communication to the UBox is established.
‹ If so, configure the firewall to allow the UBox UDP/TCP ports to pass
through. See
Firewalls below.
‹ If not, the UDP/TCP ports between the UBox and UBox application on the
PC do not match. See
Troubleshooting: UDP Ports on page 53.
Firewalls
A firewall helps keep your network safe by preventing hackers from getting inside
your network and preventing you from sending private data to outside networks (e.g.,
the Internet).
Firewalls are either hardware (a physical item on your network such as your DSL
router) or software (resides on your computer, e.g., Windows XP's built-in firewall
software). In most cases, these firewalls are configured to allow only basic Internet
traffic (e.g., web, email, ftp) to come in and out of your network. Since the UBox is a
new product, these firewalls usually do not know about Lantronix UBox network data
and may prevent you from communicating with your UBox.
UBox User Guide 54