System Diagnostics

There are four sets of diagnostics for a controller:

• Radio diagnostics
• Station diagnostics
• Inferences
• Station Connection Diagnostics (Serviceability)

Radio diagnostics

Each AP has either one or two radios that can be configured individually (Configuration > Wireless > Radio). You can check on the wireless activity trends for these radios by looking at the diagnostic information:

1. Click Monitor > Diagnostics > Radio.
2. Provide an AP number and an interface ID (Radio 1 or 2).
3. Click Start Diagnostics in the upper right corner of the screen.

Figure 80: Radio Diagnostics

1. Check the four charts for these radio trends:

Chart	What it tells you	Why you might want to know this
Throughput	Sum of upstream and downstream traffic for the radio	Users are experiencing slow response in the area covered by this AP
Noise Level	How much unwanted energy is present in the received radio signals	Users are experiencing connection problems or low transmission speeds in the region covered by this AP
Associated Stations	How many clients are using this AP	Find out if you need to add another AP (consult your reseller for specific AP deployment recommendations)
Current Value	Packet retries, loss %, channel utilization, and management overhead for the radio	Users are experiencing slow response in the area covered by this AP

Station diagnostics

Each client on an AP can be studied individually by looking at the station diagnostic information:

1. Click Monitor > Diagnostics > Station.
2. Provide a MAC address for the client. One way to determine the client MAC address on Windows XP is to open the Command Prompt by clicking Programs > Accessories > Command Prompt and then entering the command ipconfig /all – this gives you physical addresses for the wireless connections.
3. Click Start Diagnostics in the upper right corner of the screen.

Figure 81: Station Diagnostics

1. Check the four charts for these station trends:

• Throughput
• Loss %
• Signal Strength
• Airtime Utilization

2. Click Help for explanations for the charts.

Inferences

Inferences are best guesses as to what could be wrong with your wireless network. Check a controller, AP, and station by looking at the diagnostic inferences:

1. Click Monitor > Diagnostics > Inferences.
2. Optionally narrow down the list by providing a MAC address for a controller, AP, or station.

A list of recent events is listed along with corresponding details.

Figure 82: Diagnostic Inferences

The first part of the message is the issue and level of severity. In the example above, there is an IP conflict which is a critical issue. The information in a Station Entry is listed below. You can read it or alternately cut and paste the MAC address into the Station Diagnostics window. Figure 83: Decoding a Station Entry

 

Sample Station Entry Inference Rule #8 matched : IP Address Update 32 times within 360 seconds. [IP 172.27.0.198] [dhcp] [data] [AP-3 AP-3] [BSSID 00:0c:e6:3d:0b:45] [ESSID rcomm_diag] [Vlan Tag 0] [L2 State clear] [L3 State clear] [First Seen @ UTC Jun 9 13:50:22] Inference Rule #12 matched : Soft Handoff 21 times within 360 seconds. [IP 172.27.0.198] [dhcp] [data] [AP-2 AP-2] [BSSID 00:0c:e6:3d:0b:45] [ESSID rcomm_diag] [Vlan Tag 0] [L2 State clear] [L3 State clear] [First Seen @ UTC Jun 9 13:50:22]

 Information Provided

• Rule that triggered entry
• Latest IP address of station
• DHCP used
• Type of traffic (data or SIP)
• AP updated
• BSSID of Station
• ESSID of Station
• VLAN tag number
• Authentication used on L2
• Authentication used on L3
• Date problem was first seen

Station Inference Messages

Some possible station rules and messages are:

#	Station Message	Remarks
1	MAC Filter ACL Success	Station executed MAC filtering ACL authentication
2	MAC Filter ACL Failure	Station exceeded threshold of MAC filtering ACL authentication attempts

 

#	Station Message	Remarks
3	MAC Filter RADIUS Success	Station executed MAC filtering RADIUS authentication
4	MAC Filter RADIUS Failure	Station exceeded threshold of MAC filtering RADIUS authentication attempts
5	Assignment Failure	Station exceeded threshold of 802.11 assignment attempts. This could be caused by any of the following: Associated AP is not found in AP table Maximum number of stations, which varies with AP models, is exceeded Maximum number of licensed stations is exceeded Controller has not received configuration of the AP yet BSSID for a client to be assigned is not found in the BSS table AP does not have a free slot for the station RSSI is not appropriate for the station
6	WEP-key Index Mismatch	Monitor WEP-key index mismatched count (Not implemented yet)
7	Association Success	Station executed 802.11 association
8	Key Exchange Success	Station executed 802.1x key exchange
9	Key Exchange Failure	Station exceeded threshold of 802.1x key exchange attempts. An AP detected either of the following conditions of 1X authentication failure between the AP and the client; EAPoL handshaking failed EAPoL handshaking timed out Another possible cause is that Hostapd detected one of the following conditions of 1X authentication and 802.1x key exchange failure: Invalid RADIUS VLAN tag detected EAP packet failed to reach the station MIC failure occurred and both the counts of MIC failure and 802.1x key exchange failure are increased 4-way handshake timed out Group key update timed out EAP key replay counter is mismatched
10	MIC Failure	Station exceeded threshold of 802.1x MIC attempts
11	802.1x RADIUS Success	Station executed 802.1x RADIUS authentication
12	802.1x RADIUS Failure	Station exceeded threshold of 802.1x RADIUS authentication attempts
13	IP Address Update	IP address changed from valid to 0, 0 to valid, or valid to valid
#	Station Message	Remarks
14	Data Decryption Failure	Data decryption failure of RX packet occurred; attempt threshold was exceeded. Hostapd detected that Ess.MicCountermeasureData.MicCounter exceeded 1 within the MIC_COUNTERMEASURE_PERIOD (60 seconds). When this occurs, Hostapd notifies the AP to stop accepting communication from that station and disassociate the station.
15	CP Guest User Success	Station authenticated a Captive-Portal guest
16	CP Guest User Failure	Station exceeded threshold of Captive-Portal guest authentication attempts
17	CP RADIUS User Success	Station authenticated Captive-Portal user using RADIUS
18	CP RADIUS User Failure	Station exceeded threshold of Captive-Portal RADIUS user authentication attempts
19	Soft-Handoff	Station executed soft-handoff

Some possible controller inference messages are:

Controller Message	What it tells you
DHCP server reached	DHCP Server required for IP address assignment is reachable
DHCP server unreachable	DHCP Server required for IP address assignment is unreachable
Gateway reached	Default gateway for client sub-network is reachable
Gateway unreachable	Default gateway for client sub-network is unreachable
RADIUS server reached	RADIUS server required for client authentication is reachable
RADIUS server unreachable	RADIUS server required for client authentication is unreachable
VLAN gateway reached	VLAN gateway in the path for client communication is reachable
VLAN gateway unreachable	VLAN gateway in the path for client communication is unreachable
IP Address conflict between wireless clients or between wired and wireless clients or between wireless client and controller	At least two wireless clients or controllers have been assigned (or have specified) the same IP address, which is causing network confusion.
IP un-assignment of client by failure of DHCP IP assignment	An IP address has been removed from the client due to the DHCP server failing to provide an assignment.