User's Manual

Troubleshooting
Tsunami QB-8100 Series (100 Mbps/5 Mbps Models) Installation and Management Guide 196
8.4.15 Changes Do Not Take Effect
Changes made in the Web Interface do not take effect:
1. Restart your Web browser.
2. Log into the radio unit again and make changes.
3. Reboot the radio unit when prompted to do so.
4. Click Commit for the changes to take effect.
Wait until the reboot is completed before accessing the unit again.
8.4.16 Link Problems
While wireless networking emerges more and more, the number of wireless connections to networks grows every day. To
successfully use the connections, technicians must be able to troubleshoot the system effectively. This section gives hints on
how a point-to-point network could be analyzed in the case of “no link”, a situation in which the customer thinks that the
link is down because there is no traffic being passed.
The four general reasons that a wireless link may not work are related to:
• Hardware
• Configuration
• Path issues (such as distance, cable loss, obstacles)
• Environment (anything that is outside the equipment and not part of the path itself)
You have tested the equipment in the office and have verified that the hardware and configurations are sound. The path
calculation has been reviewed, and the path has been double-checked for obstacles and canceling reflections. Still, the user
reports that the link does not work.
Most likely, the problem reported is caused by the environment or by improper tests to verify the connection. The test
method, cabling, antennas, and antenna alignment have been checked. Always do this before checking the environment.
8.4.17 General Check
Two general checks are recommended before taking any action:
• Check whether the software version on all devices is the most current version.
• Check for any reported alarm messages in the Event Log.
8.4.18 Statistics Check
Interference and other negative environment factors always have an impact on the number of correctly received frames. The
Tsunami QB-8100 models give detailed information about transmission errors in the Web interface, under Monitor
(Section/Window etc.).
The windows that are important for validating the health of the link are:
• Monitor / Wireless Statistics: Check CRC errors: Rising CRC errors indicate interference or low fade margin. So does
Failed count. If only one of those is high, this indicates that a source of interference is significant near one end of the
link.
• Monitor / Ethernet Statistics: The information is given after the wireless Ethernet frame is converted into a normal
Ethernet frame. The parameters shown are part of the MIB-II.
– Both operational and admin status should be up. An admin status of down indicates that the interface is configured
to be down.
– In Discards and Out Discards indicate overload of the buffers, likely caused by network traffic, which is too heavy.