WMAX Troubleshooting Guide_070902

8/3/2019 WMAX Troubleshooting Guide_070902

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WMAX

Troubleshooting Guide

SW Version 2.5September 2007P/N 214693


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ii WMAX Troubleshooting Guide

Document History

Docum ent H is to r y

No. Topic Description Date Issued

1 General This is the first release of this guide. SW Version 2.0,

February 2006

2 Rates vs. SNR Table Section 8 Modulation and Coding column

updated

SW Version 2.0, Rev. B,

March 2006

3 General Format Update SW Version 2.5,

June 2006


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Contents

1 SU Ethernet Port Connect ion Problem (No Telnet) . .. .. .. .. .. .. .. .. .. .. .1

2 NPU Data Por t Connec t ion Prob lem (No Management ) . ..... .... ..... .2

3 TRAPs Sending Proble m ................................................................ 3

4 SU Asso c iat ion Proble m ................................................................ 3

5 SU Data Connec t ivi t y Proble m ...................................................... 4

6 Dow nli nk Tra ffi c Proble m ..............................................................6

7 Upli nk Tra ffi c Proble m ................................................................... 8

8 Rat e v s. SN R Ta bl e ...................................................................... 11


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SU Ethernet Port Connection Problem (No Telnet)

WMAX Troubleshooting Guide 1

1 SU Et hernet Por t Connec t ionProblem (No Telnet )Problem and Indication Possible Cause Corrective Action

The Ethernet Integrity

Indicator (the yellow LED

embedded in the Ethernet

connector) is off, and/or the

Ethernet Activity Indicator

(the green embedded LED)

does not blink when there

should be traffic on the

Ethernet port.

Wrong type of Ethernet

cable

If connected directly to PC-use a straight cable.

Otherwise-use a crossed cable.

Faulty Ethernet cable Replace cable

IDU-ODU cable problem. Verify that the IDU-ODU cable is in order and

connected properly. Using SAU, verify that PWR

LED is on and ALRM LED is off.

The Ethernet Activity and/or

Integrity LEDs are on, but

no Telnet access and the

unit does not respond to

ping.

Wrong IP configuration Make sure that the PC is on the same subnet as the

unit. The unit's IP address for management

purposes is 192.168.254.251, and the subnet mask

is 255.255.255.0.

Wrong Ethernet port

operation mode

Make sure that the speed and duplex settings in the

PC match the configuration in the unit. The default

operation mode is Auto Negotiation, and supported

speeds are 10/100 Mbps, Full or Half Duplex.

ARP table in the PC

contains a wrong MAC

address for the

192.168.254.251 IP

address (due to a recent

connection to another SU).

Perform arpV-d at the DOS command prompt to

clear the ARP table, and retry the Telnet command

to the unit.

Bridging table in SU is full

(expected when Number of

Supported Devices,

configurable from the Base

station's side, is set to a

small number.

Reset the SU to clear the table and retry the Telnet

command to the unit.


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2 WMAX Troubleshooting Guide

Troubleshooting

2 NPU Dat a Por t Connec t ion Problem(No Managem ent )Problem and Indication Possible Cause Corrective Action

No NPU Management

Connection

Troubleshoot via the

Monitor program, using the

MON Serial port)

Assumptions:

Management should be

done via the Data port (In

Band) ONLY

1 Verify that the Management port is

disconnected. Verify that the IP address of the

Management port is other than 0.0.0.0.

2 Check the IP parameters of Data port and try to

ping it. The default IP address is 1.1.1.3 with

subnet mask 255.255.255.0.

3 Verify that the Data Port Management Traffic

parameter is Enabled.

4 Verify that the Data Port Status is Up. If not,

check that the Ethernet cable is straight/crossed,

according to the connected equipment: Crossed

when connected directly to a PC, straight

otherwise.

5 Verify that the Data Port Speed (100 Mbps or 1

Gbps) is compatible with the equipment

connected.

6 Verify that the Data Port Management VLAN ID

matches the Management VLAN ID of theconnected equipment. The default is None (No

VLAN).

7 When working in SNMP, verify that the IP

address of the device connecting to the

management system is configured as an

Authorized Manager, and that the Read/Write

communities configured in the Authorized

Manager entry complies with the community

strings used by the connected device.

8 If connecting from a different subnet, verify that

the Management Port Dest Subnet andManagement 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).


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TRAPs Sending Problem


3 TRAPs Sending Problem

4 SU Assoc ia t ion Problem

Problem and Indication Possible Cause Corrective Action

No Traps (Management is

OK)

Configuration problem Verify that the Send Traps parameter in the

Authorized Manager entry for the managing device

is set to Enable.

Verify that the Admin Status of relevant traps in the

Trap Configuration menu is set to Enable.

If connecting from a different subnet, 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 portand does not go out through the Management port).


No Association - No Link

(WLNK LED in SAU is off)

Assumptions:

The Base Station, including

the applicable AU, is up and

running properly.

At least 1 SU is associated

with the applicable AU.

The SU, AU and NPU use

the latest SW version.

No power to the SU-IDU 1 Check that the power cable is connected.

2 Verify proper output power on the power cable

connector.

3 Replace power cable.

SU-ODU is disconnected 1 Verify that the IDU-ODU cable is connected.

2 Using SAU, check that the PWR LED is on and

that the ALRM LED is off.

Wrong configuration at SU

side

1 Open a Telnet session to the SU. Verify that the

unit is connected.

2 Verify that the unit's configuration matches the

AU configuration: Frequency, Bandwidth, Base

Station ID parameters.

The antenna bearing is not

optimal.

Slowly align the antenna towards the Base Station

while checking the SAU's LINK Bar LEDs.

Severe NLOS conditions. Check that the location of the SU is according to the

radio planning.


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Troubleshooting

5 SU Dat a Connec t iv i t y ProblemProblem and Indication Possible Cause Corrective Action

No Data Connectivity

Assumptions:

Link with the Base Station

has been established.

User's data equipment

connectivity is OK.

Base Station is up and

running properly, at leastone SU receives data.

Bridging table in SU is full

(expected when Number of

Supported Devices,

configurable from the Base

station's side, is set to a

small number.

Reset the SU to clear the table and retry the Telnet

command to the unit.

SU Status Configuration

problem

1 Ping the ISP's Local IP/Default Gateway.

2 In the Base Station, find the SU according to its

MAC address and check that the Registration

Status of the SU is "In Service".

3 Check that the Service Fault Status of the SU is

OK. Otherwise, refer to SU Service Fault

reasons below.

4 Check the Status of the SU:

a SU is Temporary and the Base station

Service Mode is Advanced: the SU will not

receive services. Change the SU Status to

Permanent and configure services.

b 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).

c SU is Permanent: check that a service is

configured for the SU's MAC address (in theServices menu).

Filtering configuration

problem

1 Verify that the MAC Address of the data

equipment is not included in the MAC Address

Deny List.

2 Verify that traffic to/from the data equipment is

not rejected due to any of the active filtering

rules.


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SU Data Connectivity Problem


Service Configuration

Problem

Check proper Service configuration:

1 Verify that the Admin Status of the Service is

Enabled.

2 Verify that the Admin Status of the Subscriber is

Enabled.

3 Verify that Operation Status is Up. If Down, the

SU may not be associated (refer to the "SU

Association Problem" above).

4 Make sure that the traffic you forward from the

equipment connected to the SU is with the

appropriate VLAN, matching the Service's

definitions for VLAN List and Hybrid VLAN

Mode.

Service Profile

configuration problem

1 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).

2 Check the Service Type - if configured as

PPPoE, make sure you are sending PPPoE

packets only.

Forwarding Rule


Check the "Unknown Forwarding Policy"

configuration; if configured to "Reject", 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).

Priority Classifier


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: 802.1p (VLAN

Traffic only) or DSCP (packets containing DSCP).

If more than one Uplink/Downlink Upper Range is

defined, packets must carry either 802.1p or DSCP

marking. Verify that the equipment behind the SUsupports the correct marking.

QoS Starvation problem Check the QoS configured for the Service. If a low

QoS (BE or NRT) is configured, the cell might be

overloaded with higher priority traffic. For testing

purposes, reconfigure a QoS with higher priority,

such as RT with CIR=12,000 Kbps, and repeat the

test.

Service Fault Status

indicates a Loop problem

A loop was detected on the

Ethernet side of the SU.

Correct the loop problem and reset the SU from the

Base Station's side.



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Troubleshooting

6 Dow nl ink Traf f ic Prob lemService Fault Status

indicates Duplicate SU

Name problem.

The Name configured in the

SU is already in use by

another SU.

Configure a new, unique name for the SU and reset

it.


High SNR, Low Rate in

Downlink (SU)

Check the Downlink SNR

and Rate of the SU. TheRate is lower than expected

according to the Rate

vs.SNR table (below)

Multirate algorithm has not

stabilized yet

Run downlink traffic via the unit for approximately 5

minutes and recheck the rate.

Installation problem Verify proper installation (including antenna

alignment and distance from objects that may affectlink quality) and when the installation is stable reset

the SU, run downlink traffic for 5 minutes and

recheck the rate.

In addition to the Rate

being lower than expected,

the Burst Error Rate at the

expected Rate is too high.

Interference Due to interference the SU cannot reach the

expected rate. Try to identify source of interference.

If feasible, try a different frequency (AU).

Check for interferences using a spectrum analyzer.

Check the radio planning.

The Burst Error Rate at the

expected Rate is low.

SU-ODU problem Replace the SU-ODU and recheck.

The problem exists also in

neighboring SUs, a single

ODU is connected to the

AU.

AU problem or high

interference

1 Check the LEDs of the AU-ODU and

AU-IDU/Micro Base Station.

2 Try to use the second Channel: If the problem

remains, replace the ODU. If the problem still

exists, replace the IDU.

If the problem disappeared after switching to the

second channel, the problem is in the channel. It

is recommended to replace the IDU.

3 If feasible, try a different frequency.

4 Check for interferences using a spectrum

analyzer.

5 Check the radio planning.



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Downlink Traffic Problem



neighboring SUs, two

ODUs are connected to the

AU/Micro Base Station and

the problem occurs only in

SUs served by one of the

ODUs.

IDU or ODU problem, or

high interference

Check the LEDs of the AU-ODU and AU-IDU/Micro

Base Station.

If feasible, try a different frequency.

Try to switch between the two ODUs (to identify a

possible problem in one of the channels). If the

same ODU remains problematic, replace the ODU.

If the problem is identified in the channel (exists now

in the SUs served by the other ODU) - replace the

AU-IDU.




neighboring SUs, two



the problem occurs in SUs

served by both ODUs..

AU-IDU/Micro Base Station

problem or high

interference on both

channels.

Check the LEDs of the AU-ODUs and AU-IDU/Micro

Base Station.

Replace the AU-IDU/Micro Base Station.





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Troubleshooting

7 Upl ink Traf f ic ProblemProblem and Indication Possible Cause Corrective Action

High SNR, Low Rate in

Uplink (SU)

Check the Uplink SNR and

Rate of the SU. The Rate is

lower than expected

according to the Rate

vs.SNR table (below).

Problem occurs in all SUs

served by the AU/Micro

Base station, the AU/Micro

Base station is connected

to a single ODU.

AU/Micro Base Station (IDU

or ODU) malfunction or

strong interference

1 Reset the AU and check the rate.

2 Verify (via counters) that uplink traffic runs

through the AU.

3 If the Burst Error Rate at the expected rate is

low, try to use the other channel. If the problem

remains, replace the ODU and recheck. If the

problem does not exist any more, the problem is

in the Channel. It is recommended to replace the

AU-IDU/Micro Base Station.

4 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.

b Change the Channel's and SU frequencies

(this can be done for a number of SUs only)

and check the rate. Note: select an available

frequency as distant as possible from the

original frequency. If the rate has improved,

check the radio planning.

c Synchronize the SU to the AU/Micro Base

station and recheck the rate.

d Perform Spectrum measurements on the

Channel's new frequency. If no interferences

are exhibited, replace the ODU and recheck.

If the problem did not disappear, replace the

IDU and recheck.


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Uplink Traffic Problem


Problem occurs in all SUs

served by the ODU. The

AU/Micro Base Station is

connected to two ODUs,

the problem occurs only in

SUs served by one of the

ODUs.

AU/Micro Base Station (IDU

or ODU) malfunction or

strong interference

1 Reset the AU/Micro Base Station and check the

rate.


through the AU/Micro Base Station.


low, try to switch between the channels. If the

problem remains in the SUs served by the same

ODU, replace the ODU and recheck. If the

problem exists now in SUs served by the other

ODU, the problem is in the Channel. Replace the

AU-IDU/Micro Base Station and recheck.


too high:


ODU disconnected and check for

interferences on the Channel's frequency.

b Change the Channel and SU frequencies

(this can be done for a number of SUs only)

and check the rate. Note: select an available

frequency as distant as possible from the

original frequency. If the rate has improved,

check the radio planning.


Station and check the rate.

d Perform Spectrum measurements on the

Channel's new frequency. If no interferences

are exhibited, replace the ODU and recheck.

If the problem did not disappear, replace the

IDU and recheck.



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Troubleshooting

The problem exists in all

SUs served by the

AU/Micro Base Station, two



the problem occurs in SUs

served by both ODUs..

AU-IDU/Micro Base Station

problem or high

interference on both

channels.

1 Reset the AU/Micro Base Station and check the

rate.


through the AU/Micro Base Station.


low, replace the AU-IDU/Micro Base Station and

recheck.


too high:


ODUs disconnected and check for

interferences on the Channel's frequencies.

b Change the Channels and SUs frequencies

(this can be done for a number of SUs only

for each sector) and check the rate. Note:

select aavailable frequencies as distant as

possible from the original frequencies. If the

rate has improved, check the radio planning.


Station and check the rate.

d Perform Spectrum measurements on theChannels' new frequencies. If no

interferences are exhibited, replace the IDU

and recheck.

Problem occurs in a single

SU

Multirate algorithm has not

stabilized yet

Run downlink traffic via the unit for approximately 5

minutes and recheck the rate.

Installation problem Verify proper installation (including antenna

alignment and distance from objects that may affect

link quality) and when the installation is stable reset

the SU, run downlink traffic for 5 minutes and

recheck the rate.

In addition to the Rate

being lower than expected,

the Burst Error Rate at the

expected Rate is too high.

Interference Due to interference the SU cannot reach the

expected rate. Try to identify source of interference.

If feasible, try a different frequency.



The Burst Error Rate at the

expected Rate is low.

SU-ODU problem Replace the SU-ODU and recheck.



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Rate vs. SNR Table


8 Rat e vs. SNR TableRate Modulation & Coding Minimum SNR (dB)

1 BPSK 1/2 3.3

2 BPSK 3/4 5.5

3 QPSK 1/2 6.5

4 QPSK 3/4 8.9

5 QAM16 1/2 12.2

6 QAM16 3/4 15

7 QAM64 2/3 19.8

8 QAM64 3/4 21


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Documents

WMAX Troubleshooting Guide_070902