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WMAX

Troubleshooting Guide

SW Version 2.5 September 2007 P/N 214693

Date Issued SW Version 2. Rev. 1 Topic General Rates vs. March 2006 SW Version 2. February 2006 SW Version 2. SNR Table Section 8 Description This is the first release of this guide.5. B.Document History Document History No.0.0. June 2006 2 Modulation and Coding column updated Format Update 3 General ii WMAX Troubleshooting Guide .

......................................................... SNR Table ................ 2 TRAPs Sending Problem ............Contents 1 2 3 4 5 6 7 8 SU Ethernet Port Connection Problem (No Telnet) ........................ 1 NPU Data Port Connection Problem (No Management)............... 4 Downlink Traffic Problem ................ 3 SU Data Connectivity Problem ....................................................................... 3 SU Association Problem ................................................................................................................................................. 6 Uplink Traffic Problem............. 8 Rate vs.............................. 11 ......................

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and retry the Telnet command to the unit. The Ethernet Activity and/or Integrity LEDs are on.168. is set to a small number.168. and/or the Ethernet Activity Indicator (the green embedded LED) does not blink when there should be traffic on the Ethernet port. The unit's IP address for management purposes is 192. Wrong IP configuration Make sure that the PC is on the same subnet as the unit. but no Telnet access and the unit does not respond to ping. Bridging table in SU is full (expected when Number of Supported Devices. Using SAU.255.SU Ethernet Port Connection Problem (No Telnet) 1 SU Ethernet Port Connection Problem (No Telnet) Possible Cause Wrong type of Ethernet cable Faulty Ethernet cable IDU-ODU cable problem. Perform arpV-d at the DOS command prompt to clear the ARP table. WMAX Troubleshooting Guide 1 . Full or Half Duplex. Reset the SU to clear the table and retry the Telnet command to the unit. verify that PWR LED is on and ALRM LED is off.255.0. and supported speeds are 10/100 Mbps. The default operation mode is Auto Negotiation. Make sure that the speed and duplex settings in the PC match the configuration in the unit. and the subnet mask is 255. Problem and Indication The Ethernet Integrity Indicator (the yellow LED embedded in the Ethernet connector) is off. Wrong Ethernet port operation mode ARP table in the PC contains a wrong MAC address for the 192.251. configurable from the Base station's side. Corrective Action If connected directly to PC-use a straight cable. Replace cable Verify that the IDU-ODU cable is in order and connected properly.251 IP address (due to a recent connection to another SU). Otherwise-use a crossed cable.254.254.

0. using the MON Serial port) Assumptions: 2 3 Management should be done via the Data port (In Band) ONLY 4 5 6 7 8 2 WMAX Troubleshooting Guide . Verify that the Data Port Speed (100 Mbps or 1 Gbps) is compatible with the equipment connected. Verify that the Data Port Management Traffic parameter is Enabled. and that the Read/Write communities configured in the Authorized Manager entry complies with the community strings used by the connected device. check that the Ethernet cable is straight/crossed. If not.255. Check the IP parameters of Data port and try to ping it.1. verify that the IP address of the device connecting to the management system is configured as an Authorized Manager.0. Verify that the IP address of the Management port is other than 0. according to the connected equipment: Crossed when connected directly to a PC.3 with subnet mask 255. Problem and Indication No NPU Management Connection Troubleshoot via the Monitor program. If connecting from a different subnet. The default is None (No VLAN).0.0. Verify that the Data Port Status is Up. straight otherwise. verify that the Management Port Dest Subnet and Management Port Dest Subnet Mask are defined correctly (to ensure that the reply is routed through the Data port and does not go out through the Management port).1. When working in SNMP. Verify that the Data Port Management VLAN ID matches the Management VLAN ID of the connected equipment.255.Troubleshooting 2 NPU Data Port Connection Problem (No Management) Possible Cause Corrective Action 1 Verify that the Management port is disconnected. The default IP address is 1.

If connecting from a different subnet. The SU. Verify proper output power on the power cable connector. Slowly align the antenna towards the Base Station while checking the SAU's LINK Bar LEDs. 4 SU Association Problem Possible Cause No power to the SU-IDU Problem and Indication No Association . Corrective Action 1 2 Check that the power cable is connected. Using SAU. Verify that the unit's configuration matches the AU configuration: Frequency. Verify that the Admin Status of relevant traps in the Trap Configuration menu is set to Enable. AU and NPU use the latest SW version. including the applicable AU. Severe NLOS conditions. Verify that the unit is connected. Base Station ID parameters. check that the PWR LED is on and that the ALRM LED is off. WMAX Troubleshooting Guide 3 . Bandwidth. Check that the location of the SU is according to the radio planning. verify that the Management Port Dest Subnet and Management Port Dest Subnet Mask are defined correctly (to ensure that the reply is routed through the Data port and does not go out through the Management port). is up and running properly.No Link (WLNK LED in SAU is off) Assumptions: The Base Station. Replace power cable.TRAPs Sending Problem 3 TRAPs Sending Problem Possible Cause Configuration problem Problem and Indication No Traps (Management is OK) Corrective Action Verify that the Send Traps parameter in the Authorized Manager entry for the managing device is set to Enable. Verify that the IDU-ODU cable is connected. At least 1 SU is associated with the applicable AU. Open a Telnet session to the SU. 3 SU-ODU is disconnected 1 2 Wrong configuration at SU side 1 2 The antenna bearing is not optimal.

In the Base Station. Check that the Service Fault Status of the SU is OK. SU is Temporary and the Base station Service Mode is Quick: Check that the applicable Default L2/PPPoE Service is configured (in the Services menu). Verify that traffic to/from the data equipment is not rejected due to any of the active filtering rules. configurable from the Base station's side. Corrective Action Reset the SU to clear the table and retry the Telnet command to the unit. 3 4 b c Filtering configuration problem 1 Verify that the MAC Address of the data equipment is not included in the MAC Address Deny List. User's data equipment connectivity is OK. Change the SU Status to Permanent and configure services.Troubleshooting 5 SU Data Connectivity Problem Possible Cause Bridging table in SU is full (expected when Number of Supported Devices. Base Station is up and running properly. SU Status Configuration problem 1 2 Ping the ISP's Local IP/Default Gateway. Check the Status of the SU: a SU is Temporary and the Base station Service Mode is Advanced: the SU will not receive services. refer to SU Service Fault reasons below. find the SU according to its MAC address and check that the Registration Status of the SU is "In Service". Otherwise. Problem and Indication No Data Connectivity Assumptions: Link with the Base Station has been established. is set to a small number. SU is Permanent: check that a service is configured for the SU's MAC address (in the Services menu). 2 4 WMAX Troubleshooting Guide . at least one SU receives data.

make sure you are sending PPPoE packets only. Correct the loop problem and reset the SU from the Base Station's side. 2 3 4 Service Profile configuration problem 1 2 Forwarding Rule configuration problem Check the "Unknown Forwarding Policy" configuration. run Uplink traffic (SU to Base Station) before running Downlink Traffic (in order to update the Base station's bridging table (addresses behind the SU). if configured to "Reject". WMAX Troubleshooting Guide 5 . and repeat the test. Verify that the traffic from the user's data equipment to the SU is with the correct priority marking as defined in the Priority Classifier: 802. packets must carry either 802. Verify that the equipment behind the SU supports the correct marking. For testing purposes. matching the Service's definitions for VLAN List and Hybrid VLAN Mode.SU Data Connectivity Problem Problem and Indication Possible Cause Service Configuration Problem Corrective Action Check proper Service configuration: 1 Verify that the Admin Status of the Service is Enabled. Service Fault Status indicates a Loop problem A loop was detected on the Ethernet side of the SU. Check the Service Type .1p (VLAN Traffic only) or DSCP (packets containing DSCP). If more than one Uplink/Downlink Upper Range is defined.1p or DSCP marking. Priority Classifier configuration problem QoS Starvation problem Check the QoS configured for the Service.if configured as PPPoE. Make sure that the traffic you forward from the equipment connected to the SU is with the appropriate VLAN. Verify that the equipment connected to the Data port of the Base Station supports the configured VPL ID (if VLAN Transparency Mode is Off) or the VLAN ID used by the equipment connected to the SU (if VLAN Transparency Mode is On). such as RT with CIR=12.000 Kbps. Verify that Operation Status is Up. Verify that the Admin Status of the Subscriber is Enabled. If a low QoS (BE or NRT) is configured. If Down. reconfigure a QoS with higher priority. the cell might be overloaded with higher priority traffic. the SU may not be associated (refer to the "SU Association Problem" above).

Low Rate in Downlink (SU) Check the Downlink SNR and Rate of the SU. Corrective Action Run downlink traffic via the unit for approximately 5 minutes and recheck the rate. run downlink traffic for 5 minutes and recheck the rate. a single ODU is connected to the AU. Possible Cause The Name configured in the SU is already in use by another SU. The Rate is lower than expected according to the Rate vs. Corrective Action Configure a new. 2 3 4 5 6 WMAX Troubleshooting Guide . The problem exists also in neighboring SUs. try a different frequency. Check for interferences using a spectrum analyzer. try a different frequency (AU). Verify proper installation (including antenna alignment and distance from objects that may affect link quality) and when the installation is stable reset the SU. unique name for the SU and reset it. If the problem disappeared after switching to the second channel. Check for interferences using a spectrum analyzer. replace the IDU. It is recommended to replace the IDU. 6 Downlink Traffic Problem Possible Cause Multirate algorithm has not stabilized yet Installation problem Problem and Indication High SNR. Try to identify source of interference. Check the radio planning. the Burst Error Rate at the expected Rate is too high. Due to interference the SU cannot reach the expected rate. Interference The Burst Error Rate at the expected Rate is low. If the problem still exists.Troubleshooting Problem and Indication Service Fault Status indicates Duplicate SU Name problem. Try to use the second Channel: If the problem remains. the problem is in the channel. If feasible. AU problem or high interference 1 Check the LEDs of the AU-ODU and AU-IDU/Micro Base Station. Check the radio planning.SNR table (below) In addition to the Rate being lower than expected. replace the ODU. SU-ODU problem Replace the SU-ODU and recheck. If feasible.

Check the LEDs of the AU-ODUs and AU-IDU/Micro Base Station. If the same ODU remains problematic. Check for interferences using a spectrum analyzer. two ODUs are connected to the AU/Micro Base Station and the problem occurs in SUs served by both ODUs. If the problem is identified in the channel (exists now in the SUs served by the other ODU) .. try a different frequency. AU-IDU/Micro Base Station problem or high interference on both channels. Replace the AU-IDU/Micro Base Station. Check for interferences using a spectrum analyzer. two ODUs are connected to the AU/Micro Base Station and the problem occurs only in SUs served by one of the ODUs. If feasible.Downlink Traffic Problem Problem and Indication The problem exists also in neighboring SUs. The problem exists also in neighboring SUs. or high interference Corrective Action Check the LEDs of the AU-ODU and AU-IDU/Micro Base Station. WMAX Troubleshooting Guide 7 .replace the AU-IDU. Possible Cause IDU or ODU problem. Check the radio planning. Try to switch between the two ODUs (to identify a possible problem in one of the channels). replace the ODU. Check the radio planning.

check the radio planning. Low Rate in Uplink (SU) Check the Uplink SNR and Rate of the SU. 3 4 b c d 8 WMAX Troubleshooting Guide . replace the ODU and recheck. replace the IDU and recheck. Change the Channel's and SU frequencies (this can be done for a number of SUs only) and check the rate. try to use the other channel.SNR table (below). AU/Micro Base Station (IDU or ODU) malfunction or strong interference 1 2 Reset the AU and check the rate. It is recommended to replace the AU-IDU/Micro Base Station. Problem occurs in all SUs served by the AU/Micro Base station. If the problem remains. Verify (via counters) that uplink traffic runs through the AU. If the problem did not disappear. If the Burst Error Rate at the expected Rate is too high: a Perform Spectrum measurements with the ODU disconnected and check for interferences on the Channel's frequency. the problem is in the Channel. Perform Spectrum measurements on the Channel's new frequency. If the Burst Error Rate at the expected rate is low. If no interferences are exhibited. If the problem does not exist any more. The Rate is lower than expected according to the Rate vs. Note: select an available frequency as distant as possible from the original frequency.Troubleshooting 7 Uplink Traffic Problem Possible Cause Corrective Action Problem and Indication High SNR. If the rate has improved. replace the ODU and recheck. Synchronize the SU to the AU/Micro Base station and recheck the rate. the AU/Micro Base station is connected to a single ODU.

If no interferences are exhibited. replace the ODU and recheck. Note: select an available frequency as distant as possible from the original frequency. Verify (via counters) that uplink traffic runs through the AU/Micro Base Station. If the problem exists now in SUs served by the other ODU. If the problem did not disappear. replace the IDU and recheck. the problem is in the Channel. the problem occurs only in SUs served by one of the ODUs. The AU/Micro Base Station is connected to two ODUs. 2 3 4 b c d WMAX Troubleshooting Guide 9 . Possible Cause AU/Micro Base Station (IDU or ODU) malfunction or strong interference Corrective Action 1 Reset the AU/Micro Base Station and check the rate. If the Burst Error Rate at the expected Rate is too high: a Perform Spectrum measurements with the ODU disconnected and check for interferences on the Channel's frequency. If the Burst Error Rate at the expected rate is low. Replace the AU-IDU/Micro Base Station and recheck. try to switch between the channels.Uplink Traffic Problem Problem and Indication Problem occurs in all SUs served by the ODU. If the problem remains in the SUs served by the same ODU. check the radio planning. replace the ODU and recheck. Change the Channel and SU frequencies (this can be done for a number of SUs only) and check the rate. If the rate has improved. Perform Spectrum measurements on the Channel's new frequency. Synchronize the SU to the AU/Micro Base Station and check the rate.

the Burst Error Rate at the expected Rate is too high. Possible Cause AU-IDU/Micro Base Station problem or high interference on both channels. 10 WMAX Troubleshooting Guide . Change the Channels and SUs frequencies (this can be done for a number of SUs only for each sector) and check the rate. If feasible. two ODUs are connected to the AU/Micro Base Station and the problem occurs in SUs served by both ODUs. Note: select aavailable frequencies as distant as possible from the original frequencies. Due to interference the SU cannot reach the expected rate. If no interferences are exhibited. If the rate has improved. Verify (via counters) that uplink traffic runs through the AU/Micro Base Station.Troubleshooting Problem and Indication The problem exists in all SUs served by the AU/Micro Base Station. 2 3 4 b c d Problem occurs in a single SU Multirate algorithm has not stabilized yet Installation problem Run downlink traffic via the unit for approximately 5 minutes and recheck the rate. Try to identify source of interference. Perform Spectrum measurements on the Channels' new frequencies. Synchronize the SU to the AU/Micro Base Station and check the rate. Check the radio planning. replace the IDU and recheck. replace the AU-IDU/Micro Base Station and recheck. If the Burst Error Rate at the expected rate is low. Interference The Burst Error Rate at the expected Rate is low. If the Burst Error Rate at the expected Rate is too high: a Perform Spectrum measurements with the ODUs disconnected and check for interferences on the Channel's frequencies. SU-ODU problem Replace the SU-ODU and recheck. In addition to the Rate being lower than expected. Verify proper installation (including antenna alignment and distance from objects that may affect link quality) and when the installation is stable reset the SU. Check for interferences using a spectrum analyzer. check the radio planning. Corrective Action 1 Reset the AU/Micro Base Station and check the rate. run downlink traffic for 5 minutes and recheck the rate. try a different frequency..

5 6.Rate vs. SNR Table 8 Rate vs.8 21 WMAX Troubleshooting Guide 11 . SNR Table Rate 1 2 3 4 5 6 7 8 Modulation & Coding BPSK 1/2 BPSK 3/4 QPSK 1/2 QPSK 3/4 QAM16 1/2 QAM16 3/4 QAM64 2/3 QAM64 3/4 Minimum SNR (dB) 3.3 5.2 15 19.9 12.5 8.