Wireless Client Troubleshooting using the Unleashed Diagnostic Tools

Vásquez_Fer — Fri, 15 Nov 2024 21:11:21 GMT

This is a brief demonstration of how to use Unleashed tools to troubleshoot a basic connectivity issue on the network on end devices.

1. Client Connection Troubleshooting

Link as reference https://docs.commscope.com/bundle/unleashed-200.16-troublshootingref/page/GUID-5BBF52D0-939D-416F-B696-FABB12AC5EE9.html

This is a demonstration for the client troubleshooting.

Select Clients, and then click the Troubleshooting button.

Figure 1: Clients Tab

Here, we can enter the MAC address of the client device in the specified format to begin troubleshooting process. If the device is already connected to the network, simply click on it, and the troubleshooting process will begin automatically.

Figure 2: Troubleshooting button.

Identify the MAC Address: Obtain the MAC address of the client device you want to analyze. Ensure you have this information handy as it will be used to filter the capture.

Input the MAC address of the client device into the designated filter.

Click the Start button to begin the troubleshooting.

In this demonstration I will use the following Mac-address for one of my Wireless clients 62:b6:b1:eb:09:89

Figure 3: Start Troubleshooting Process

Once you click Start, no data will be displayed initially because the device has not yet connected to the network or attempted to connect to any of the AP's SSIDs.

Figure 4: Troubleshooting Process

In this example, I will attempt to connect my end client to the SSID of the Access Point and intentionally use an incorrect password.

Figure 5: Initial Packet Capture View

First, we will analyze what we are observing firsthand during this test. We can identify which Access Point the end device is connecting to, the band it is using (whether 2.4 GHz or 5 GHz), and in this case, it is 5 GHz on channel 157. Additionally, we can observe the environmental SNR and the timestamp of the events according to the Access Point's log.

Now we will analyze the packets exchanged between the end client and the Access Point.

Figure 6: Analysis of Packet Exchange Between Client and Access Point

The client device initiates the connection by sending authentication and association requests, which the AP responds to. During the 4-way handshake, each attempt fails repeatedly, suggesting there is an issue. After multiple failures, the AP deauthenticates the client, ending the connection attempt.

Figure 7: Final Analysis - Client Failed Handshake

When the Information button on the error is pressed, it often provides a suggested error code and status, which can also be copied for reference. In this example, the tool indicates an "invalid passphrase" error, accurately reflecting the intentional use of an incorrect password for testing purposes. This tool is highly effective for troubleshooting connectivity issues, as it provides insights into client behavior during the authentication process, in roaming scenarios, and across various other network situations.

2. Capturing Remote Packets

Remote packet capture enables one or more APs to operate in packet sniffer mode, allowing them to capture wireless packets on the network. These packets can either be saved locally on the device or streamed in real time to a packet analysis tool, such as Wireshark, for detailed inspection and troubleshooting. This feature is valuable for diagnosing connectivity issues and monitoring network performance by analyzing the captured packet data.

Link as reference https://docs.commscope.com/bundle/unleashed-200.16-onlinehelp/page/GUID-FE747C7C-8F63-409B-A423-63F898CA8331.html

Go to Admin & Services > Administration > Diagnostics > Packet Capture.

Figure 8: Packet capture tab

In this section, we will find the Access Points in our network, along with their model, device name, and corresponding IP address.

To troubleshoot the client connectivity issue, select the desired APs, and then choose Add to Capture. This action will move the APs to the Capture APs table.

Figure 9: Selecting the Access Point for the Packet Capture

For Radio, select either 2.4 GHz or 5 GHz/6 GHz. In this case, since we are working with a 5 GHz connection, select the 5 GHz option.

You can Select Local Mode or Streaming Mode as the capture mode:

+To capture a limited snapshot on each AP, select Local Mode.
+To stream the captured packets directly to Wireshark for real-time analysis, select Streaming Mode.

In this example we are going to select Local Mode.

In this example, since the MAC address of the problematic device is known, enter it to filter the capture data specifically for that client. Click Start to begin capturing packets. At this stage, reproduce the issue. Once the issue has been reproduced, click Stop to end the capture.

Figure 10: Initiate the Packet Capture

Then click Save to store the packet capture as a local file for later analysis.

Figure 11 : Downloaded PCAP from the Unlashed UI.

Once the file is downloaded, it will be saved in the Downloads folder. Extract the contents, and you’ll find folders containing the PCAP files. These files include detailed information on the association process for the end client , which will help you investigating if there is any incidents.

Note : Remember to remove the AP from the capture list and disable packet capture after completing this process.

By analyzing the packet exchange during the connection process, you can pinpoint where the failure occurs and take appropriate corrective actions. This method provides valuable insights into the interaction between client devices and APs in real time.

topic Wireless Client Troubleshooting using the Unleashed Diagnostic Tools in RUCKUS Self-Help

Wireless Client Troubleshooting using the Unleashed Diagnostic Tools

1. Client Connection Troubleshooting

2. Capturing Remote Packets