A Methodical Approach to WLAN Troubleshooting.
Troubleshooting any sort of network problem should follow a methodical approach, it’s highly recommended that you start by working up the TCP/IP stack from the layer 1 (Physical layer) to the layer 7 (Application layer). This helps to eliminate any issue that you may be able to resolve yourself.
There are three steps of the methodical troubleshooting approach when working with Wireless Ethernet LANs.
Step 1 – Eliminate the user PC as the source of the problem.
- Try to establish the severity of the problem. If there is no connectivity, verify the following:
- Use the ipconfig command to confirm the user PC network configuration. Check if the PC has received an IP address via DHCP or is configured with static IP address.
* Verify that the PC has connectivity to the wired network. Connect the device to the wired LAN and ping a known IP address.
* Try a different wireless NIC. If necessary, reload drivers and firmware as appropriate for the client device.
If the wireless NIC of the client is working, check the security mode and encryption settings on the client. If the security settings do not match, the client cannot get access to the WLAN.
* If the user PC is functioning but the performance is poor, check the following:
- How far is the PC from an access point? Is the PC out of the planned coverage area.
* Check the channel settings on the client. The client software should detect the appropriate channel as long as the SSID is correct.
* Check for the presence of other devices in the area that operates on the 2.4 GHz band. Examples of other devices are cordless phones, baby monitors, microwave ovens, wireless security systems, and potentially rogue access points. Data from these devices can cause interference in the WLAN and intermittent connection problems between a client and access point.
Step 2 – Confirm the physical status of other network devices.
- Are all the network devices actually in place?
* Check for a possible physical security issue.
* Is there power to all devices, and are they powered on?
Step 3 – Inspect physical links.
- Inspect links between cabled devices looking for bad connectors or damaged or missing cables.
If the physical plant is in place, use the wired LAN to see if you can ping devices including the access point.
If connectivity still fails at this point, there might be something wrong with the access point or its configuration.
After eliminating the user PC as the problem, and also confirmed the physical status of the network devices, begin investigating the performance of the access point. Check the power status of the access point.
When the access point settings have been confirmed, if the radio continues to fail, try to connect to a different access point. You may try to install new radio drivers and firmware.