Cisco Unified Wireless IP Phone 7925G, 7925G-EX, and 7926G Administration Guide

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Book Title

Cisco Unified Wireless IP Phone 7925G, 7925G-EX, and 7926G Administration Guide

Chapter Title

Troubleshooting

Results

Updated:
October 31, 2021

Chapter: Troubleshooting

Troubleshooting

Startup and Connectivity Problems

After installing a Cisco Unified Wireless IP Phone 7925G, 7925G-EX, and 7926G in your network and adding it to Cisco Unified Communications Manager Administration, the phone should start up as described in the Phone Startup Process. If the phone does not start up properly, see the following sections for troubleshooting information.

Incomplete Startup Process

Problem

The phone does not start up and information does not display on the phone.

Cause

When an IP Phone connects to the wireless network, the phone should go through its normal startup process and the phone screen should display information.

If the phone does not complete the startup process, the cause might be due to low RF signal strength, network outages, a dead battery in the phone, or the phone might not be functional.

Solution

To determine whether the phone is functional, follow these suggestions to systematically eliminate potential problems.

  1. Verify that the wired network is accessible by placing calls to and from other wired Cisco Unified IP Phones.

  2. Verify that the wireless network is accessible:

    • Power on another previously functional Cisco Unified Wireless IP Phone to verify that the access point is active.

    • Power on the Cisco Unified Wireless IP Phone that will not start up and move to a different access point location that is known to be good.

  3. Verify that the phone is receiving power:

    • If the message Low Battery appears on the phone screen, the battery might be dead.

    • Insert a new or fully charged battery in the wireless IP phone that will not start up.

    • If you are using the battery, try plugging in the external power supply instead.

  4. If the phone does not power up successfully, and never shows the Main screen, try using Recovery Mode:

    • Press both the Push to Talk button and the Speaker button, and then press the Power button.

    • The phone goes into recovery mode and checks the integrity of the firmware files.

    • If an error message appears indicating recovery required, then plug the USB cable into the phone and a PC. See Set Up USB LAN on PC.

    • Using a browser, access the web page for the phone. See Access Phone Web Page for instructions.

    • Go to the Phone Recovery section on the web page and upload a new Phone Software TAR file.

If, after you attempt these solutions, the phone still does not start up, contact a Cisco technical support representative for additional assistance.

No Association to Cisco Aironet Access Points

After power on, if a phone continues to cycle through messages displaying on the phone screen, the phone is not associating with the access point properly. The phone cannot successfully start up unless it associates and authenticates with an access point.

The wireless phone must first authenticate and associate with an access point before it can obtain an IP address. The phone follows this start up process with the access point:

  1. Scans for an access point

  2. Associates with an access point

  3. Authenticates using a preconfigured authentication method (using the configured security mode setting)

  4. Obtains an IP address

Access Point Settings Mismatch

Problem

A configuration mismatch exists between the phone and the AP.

Solution

  • Check the SSID settings on the access point and on the phone to be sure the SSIDs match.

  • Check the authentication type settings on the access point and on the phone to be sure authentication and encryption settings match.


    Note

    If the No Service - IP Config Failed message displays, DHCP failed because the encryption between the access point and phone do not match.

  • If using static WEP, check the WEP key on the phone to be sure it matches the WEP key on the access point. Reenter the WEP key on the phone to be sure it is correct.


    Note

    If open authentication is set, the phone is able to associate to an access point even if the WEP keys are incorrect or mismatched.

Authentication Failed, No AP Found

Problem

Authentication returns the No AP found message.

Solution

  • Check whether the correct authentication method and related encryption settings are enabled on the access point.

  • Check that the correct SSID is entered on the phone.

  • Check that the correct username and password are configured when using LEAP, EAP-FAST, PEAP, or Auto (AKM) authentication.

  • If you are using a WPA Pre-shared key or WPA2 Pre-shared Key, check that you have the correct passphrase configured.

  • You might need to enter the username on the phone in the domain\username format when authenticating with a Windows domain.

EAP Authentication Failed Message

Problem

Authentication returns the EAP authentication failed message.

Solution

  • If you are using EAP, you might need to enter the EAP username on the phone in the domain\username format when authenticating with a Windows domain.

  • Check that the correct EAP username and password are entered on phone.

AP Error - Cannot Support All Requested Capabilities

Problem

Authentication returned the AP Error - Cannot support all requested capabilities message.

Solution

On the access point, check that CKIP/CMIC is not enabled for the voice VLAN SSID. The wireless phone does not support these features.

Phone Does Not Register with Cisco Unified Communications Manager

If a phone proceeds past the first stage (authenticating with access point) and continues to cycle through the messages displaying on the phone screen, the phone is not starting up properly. The phone cannot successfully start up until it connects to the LAN and registers with a Cisco Unified Communications Manager server.

The following sections can assist you in determining the reason that the phone is unable to start up properly.

Cisco Unified Communications Manager Phone Registration Rejected

Problem

The error message Registration Rejected displays.

Cause

A Cisco Unified Wireless IP Phone can register with a Cisco Unified Communications Manager server only if the phone has been added to the server or if autoregistration is enabled.

Solution

Review the information and procedures in Add Users to Cisco Unified Communications Manager to ensure that the phone has been added to the Cisco Unified Communications Manager database. Verify that the phone is in the Cisco Unified Communications Manager database, using Device > Phone > Find from Cisco Unified Communications Manager Administration to search for the phone based on its MAC Address. To determine the MAC address of a phone, see Device Information.

If the phone is already entered in the Cisco Unified Communications Manager database, its configuration file may be damaged. See Configuration File Corruption for assistance.

Phone Cannot Connect to TFTP Server or to Cisco Unified Communications Manager

Problem

If the network is down between the phone and either the TFTP server or Cisco Unified Communications Manager, the phone cannot start up properly.

Solution

Ensure that the network is currently running.

TFTP Server Settings

Problem

The TFTP server setting on the phone is incorrect.

Cause

The Cisco Unified Wireless IP Phone uses the TFTP server setting to identify the primary TFTP server to use. If the TFTP server does not respond to the request, then the Communications Manager1 (CM1) shows as TFTP_AS_CM if the phone has not registered with Cisco Unified Communications Manager before.


Note

If the phone has previously registered with Cisco Unified Communications Manager, the Cisco Unified Communications Manager list information is cached in memory. If TFTP fails, you must power cycle the phone to connect to the TFTP server.

The phone tries to create a TCP connection to the TFTP IP address and then to the gateway. If Cisco Unified Communications Manager service is not running on the TFTP server, or if SRST is not running on the gateway, the wireless IP phone may continually cycle while attempting to contact the identified TFTP server.

The Cisco Unified Wireless IP Phone does not cache the IP information passed from the DHCP server, so the TFTP request must be sent and responded to every time the phone power cycles.

Solution

If you have assigned a static IP address to the phone, you must manually enter this setting. See IP Network Settings.

If you are using DHCP, the phone obtains the address for the TFTP server from the DHCP server. Check the IP address configured in the DHCP server.

You can also enable the phone to use a static TFTP server. Such a setting is particularly useful if the phone was recently moved from one location to another.

For information about determining and changing TFTP server settings, see IP Network Settings or View Configuration File Name.

IP Addressing and Routing

Problem

The IP addressing and routing fields may not be correctly configured.

Solution

Verify the IP addressing for the Cisco Unified Wireless IP Phone. If you are using DHCP, the DHCP server should provide these values. If you have assigned a static IP address to the phone, you must enter these values manually.


Note

When the wireless IP phone loses the RF signal (goes out of the coverage area), the phone will not release the DHCP server unless it reaches the timeout state.

Check for these problems:

  • DHCP Server: If you have assigned a static IP address to the phone, you do not need to enter a value for the DHCP Server option. If you are using a DHCP server, and the wireless IP phone gets a response from the DHCP server, the information is automatically configured. See Troubleshooting Switch Port Problems, available at this URL: http://www.cisco.com/en/US/products/hw/switches/ps708/products_tech_note09186a008015bfd6.shtml.

  • IP Address, Subnet Mask, Primary Gateway: If you have assigned a static IP address to the phone, you must configure settings for these options. See IP Network Settings.

If you are using DHCP, check the IP addresses distributed by your DHCP server. Be aware of DHCP conflicts and duplicate IP addresses. See Understanding and Troubleshooting DHCP in Catalyst Switch or Enterprise Networks, available at this URL: http://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a00800f0804.shtml.

For information about determining and changing IP addressing, see IP Network Settings .

DNS Settings

Problem

The phone has incorrect DNS server information.

Solution

If you are using DNS to refer to Cisco Unified Communications Manager, you must ensure that you have specified a DNS server. You should also verify that there is a CNAME entry in the DNS server for the Cisco Unified Communications Manager system.

You must also ensure that DNS is configured to do reverse look-ups. The default setting on Windows 2000 is to perform forward-only look-ups.

For information about determining and changing DNS settings, see IP Network Settings.

Cisco Unified Communications Manager and TFTP Service Status

Problem

If the Cisco Unified Communications Manager or TFTP services are not running, phones might not be able to start up properly. However, in such situations, it is likely that you are experiencing a system-wide failure and that other phones and devices are unable to start up properly.

Cause

The wireless phone attempts to open a TCP connection to all the Cisco Unified Communications Manager servers that are part of the assigned Cisco Unified Communications Manager group.

Solution

If the Cisco Unified Communications Manager service is not running, all devices on the network that rely on it to make phone calls will be affected. If the TFTP service is not running, many devices will not be able to start up successfully.

For more information, see the Cisco Unified Communications Manager documentation.

Configuration File Corruption

Problem

If you continue to have problems with a particular phone that other suggestions in this chapter do not resolve, the configuration file might be corrupted.

Solution

Create a new phone configuration file. See Create New Configuration File.

Cisco Unified Wireless IP Phone Resets Unexpectedly

If users report that their phones are resetting during calls or resetting while idle on their desk, you should investigate the cause. If the network connection and Cisco Unified Communications Manager connection are stable, a Cisco Unified Wireless IP Phone should not reset on its own.

Typically, a phone resets if it has problems connecting to the access point and LAN or to Cisco Unified Communications Manager. The following sections can help you identify the cause of a phone resetting in your network.

Phone Resets Due to Access Point Setup

Problem

The AP may not be configured correctly.

Solution

Verify that the wireless configuration is correct. For example, check if the particular access point or switch to which the phone is connected is down.

Intermittent Network Outages

Problem

Your network may be experiencing intermittent outages.

Solution

Intermittent network outages affect data and voice traffic differently. Your network might be experiencing intermittent outages without detection. If so, data traffic can resend lost packets and verify that packets are received and transmitted. However, voice traffic cannot recapture lost packets. Rather than retransmitting a lost network connection, the phone resets and attempts to reconnect to the network. Contact the system administrator for information on known problems in the voice network.

DHCP Settings Errors

Problem

The DHCP settings may be incorrect.

Solution

Try the following actions:

  • Verify that you have properly configured the phone to use DHCP. See Verify DHCP Setup.

  • Verify that the DHCP server is set up properly.

  • Verify the DHCP lease duration. Cisco recommends that you set the lease duration to 8 days.

Voice VLAN Setup Errors

Problem

If the Cisco Unified Wireless IP Phone appears to reset during heavy network usage (for example, following extensive web surfing on a computer connected to same access point and switch as phone), it is likely that you do not have a voice VLAN or the appropriate QoS settings configured.

Solution

By isolating the wireless phones on a separate auxiliary VLAN, you can use QoS to prioritize the voice traffic over data traffic and improve the voice quality. See Voice QoS in Wireless Networks for details.

Phones Have Not Been Intentionally Reset

Problem

If you are not the only administrator with access to Cisco Unified Communications Manager, you should verify that no one else has intentionally reset the phones.

Solution

You can check if a Cisco Unified IP Phone received a command from Cisco Unified Communications Manager to reset by pressing Applications on the phone and choosing Administrator Settings > Status > Network Statistics.

  • If the Restart Cause field displays Reset-Reset, the phone received a Reset/Reset from Cisco Unified Communications Manager Administration.

  • If the Restart Cause field displays Reset-Restart, the phone reset because it received a Reset/Restart from Cisco Unified Communications Manager Administration.

DNS or Other Connectivity Errors

Problem

The phone reset continues and you suspect DNS or other connectivity issues.

Solution

If the phone continues to reset, eliminate DNS or other connectivity errors. See Determine DNS or Connectivity Issues.

Audio Problems

When users report that active phone calls have poor voice quality that includes choppy audio, static or gaps in audio, or no audio, use the information in this section to identify the cause of the problem.

One-Way Audio or No Speech Path

Problem

One or more people on a call do not hear any audio.

Solution

Use the following list to identify possible causes for the problem:

  • Check the access point to see if the transmit power setting matches the transmit power setting on the phone. One-way audio is common when the access point power setting is greater than that of the phone.

    The phone firmware supports dynamic transmit power control (DTPC). The phone uses the transmit power that the access point advertises upon association.


    Note

    With DTPC, if Client Transmit Power is set in the access point, the phone automatically uses the same client power setting. If the access point is set for the maximum setting (Max), the access point uses the Transmit Power setting on the phone.

  • Check that the access point is enabled for ARP caching. When the phone is in power save mode or scanning, the access point can respond to the wireless IP phone only when ARP caching is enabled.

  • Check your gateway and IP routing for voice problems.

  • Check if a firewall or NAT is in the path of the RTP packets. If so, you can use Cisco IOS and PIXNAT to modify the connections so that two-way audio is possible.

  • Check that the Data Rate setting for the phone and the access point are the same. These settings should match or the phone should be set for Auto.

  • Check the phone hardware to be sure the speaker is functioning properly.

  • Check the volume settings in the Phone Settings menu.

  • Check that the speaker is functioning properly. Adjust the speaker volume setting and call the phone to check the speaker.

Ring Volume is Too Low

Problem

User complains that the ringer on the phone is not loud enough.

Solution

To see if the ring volume is set correctly on the phone, choose Settings > Phone Settings > Sound Settings > Volumes. Scroll up for the highest volume.

You can also press the Volume button on the side of the phone and the volume setting appears on the phone screen.

Phone Does Not Ring

Problem

User complains that phone does not ring.

Solution

Check the phone settings:

  • To see if the phone is set to ring, choose Settings > Phone Settings > Sound Settings > Alert Pattern, and check that a ring setting is selected.

  • To see if a ringtone has been set for the phone, choose Settings > Phone Settings > Ring Tone. If none is set, add a ringtone for the phone.

  • To see if the speaker is functioning properly, adjust the ring volume settings to the highest level. Enable keypad tones or call the phone to check the speaker.

Roaming and Voice Quality or Lost Connection Problems

If users report that when they are engaged in an active phone call and walking from one location to another (roaming), the voice quality deteriorates or the connection is lost, use the information in this section to identify the cause of the problem.

Voice Quality Deteriorates While Roaming

Problem

User complains that the voice quality deteriorates while roaming.

Solution

  • Check the RSSI on the destination access point to see if the signal strength is adequate. The next access point should have an RSSI value of -67 dBm or greater.

  • Check the site survey to determine if the channel overlap is adequate for the phone and the access point to hand off the call to the next access point before the signal is lost from the previous access point.

  • Check to see if noise or interference in the coverage area is too great.

  • Check that signal to noise ratio (SNR) levels are 25 dB or higher for acceptable voice quality.

Voice Conversation Delays While Roaming

Problem

User complains of delays in the voice conversation while roaming.

Solution

  • Use the Site Survey Utility to see if there is another acceptable access point as a roaming option. The next access point should have an signal of -67 dBm to roam successfully.

  • Check the Cisco Catalyst 45xx switch. If Cisco Catalyst 45xx series switches are being used as the main Layer 3 switches in the network, ensure that the supervisor blades are a minimum SUP2+ or later version. The wireless phone (or any wireless client) experiences roaming delays when an earlier version (SUP 1 or SUP2) blade is used.

Phone Loses Cisco Unified Communications Manager Connection While Roaming

Problem

User complains that the call gets dropped while roaming.

Solution

Check for the following configuration or connectivity issues between the phone and the access point:

  • The RF signal strength might be weak. Use the Site Survey Tool and check the RSSI value for the next access point.

  • The next access point might not have connectivity to Cisco Unified Communications Manager.

  • There might be an authentication type mismatch between the phone and the next access point.

  • The access point might be in a different subnet from the previous access point. The Cisco Unified Wireless IP Phone is capable of Layer 2 roaming only. Layer 3 roaming requires WLSM that uses GRE. For more information, see WLANs and Roaming.

  • If using EAP-FAST, LEAP, or Auto (AKM) authentication, the access point might be using filters to block TCP ports. The RADIUS server uses port 1812 for authentication and 1813 for accounting.

Phone Does not Roam Back to Preferred Band

Problem

The phone does not roam back to the preferred wireless band.

Solution

For troubleshooting information, see the Cisco Unified Wireless IP Phone 7925 and 7926 Series Deployment Guide.

Voice Quality Monitoring

To measure the voice quality of calls that are sent and received within the network, Cisco IP Phones use the following statistical metrics that are based on concealment events. The DSP plays concealment frames to mask frame loss in the voice packet stream.

Concealment Ratio metrics

Shows the ratio of concealment frames over total speech frames. An interval conceal ratio is calculated every 3 seconds.

Concealed Second metrics

Shows the number of seconds in which the DSP plays concealment frames due to lost frames. A severely "concealed second" is a second in which the DSP plays more than 5 percent concealment frames.

MOS-LQK metrics

Uses a numeric score to estimate the relative voice listening quality. The phone calculates the mean opinion score (MOS) for listening quality (LQK) based audible concealment events due to frame loss in the preceding 8 seconds, and includes perceptual weighting factors such as codec type and frame size.

MOS LQK scores are produced by a Cisco proprietary algorithm, Cisco Voice Transmission Quality (CVTQ) index. Depending on the MOS LQK version number, these scores might be compliant with the International Telecommunications Union (ITU) standard P.564. This standard defines evaluation methods and performance accuracy targets that predict listening quality scores based on observation of actual network impairment.


Note

Concealment ratio and concealment seconds are primary measurements based on frame loss while MOS LQK scores project a "human-weighted" version of the same information on a scale from 5 (excellent) to 1 (bad) for measuring listening quality.

Listening quality scores (MOS LQK) relate to the clarity or sound of the received voice signal. Conversational quality scores (MOS CQ such as G.107) include impairment factors, such as delay, that degrade the natural flow of conversation.

For information about configuring voice quality metrics for phones, see the phone metrics sections in the Cisco Unified Communications Manager documents.

You can access voice quality metrics on the phone or remotely by using Streaming Statistics.

Voice Quality Metrics

To use the metrics for monitoring voice quality, note the typical scores under normal conditions of zero packet loss and use the metrics as a baseline for comparison.

It is important to distinguish significant changes from random changes in metrics. Significant changes are scores that change about 0.2 MOS or greater and persist in calls that last longer than 30 seconds. Conceal Ratio changes should indicate greater than 3 percent frame loss.

MOS LQK scores can vary based on the codec that the phone uses. The following codecs provide these MOS LQK scores under normal conditions with zero frame loss:

  • G.711 and G.722 codecs have maximum scores of 4.5

  • G.729A/AB codec has a maximum score of 3.8

A Conceal Ratio of zero indicates that the IP network is delivering frames and packets on time with no loss.

Voice Quality Troubleshooting Tips

When you observe significant and persistent changes to metrics, use the following table for general troubleshooting information.

Table 1. Changes to Voice Quality Metrics

Metric change

Condition

MOS LQK scores decrease significantly

Network impairment from packet loss or high jitter:

  • Average MOS LQK decreases could indicate widespread and uniform impairment.
  • Individual MOS LQK decreases indicate bursty impairment.

Cross-check with Conceal Ratio and Conceal Seconds for evidence of packet loss and jitter.

MOS LQK scores decrease significantly

  • Check to see if the phone is using a different codec than expected (Sender Codec and Rcvr Codec).
  • Check to see if the MOS LQK version changed after a firmware upgrade.

Conceal Ratio and Conceal Seconds increase significantly

  • Network impairment from packet loss or high jitter.

Conceal Ratio is near or at zero, but the voice quality is poor

  • Noise or distortion in the audio channel such as echo or audio levels.
  • Tandem calls that undergo multiple encode/decode such as calls to a cellular network or calling card network.
  • Acoustic problems coming from a speakerphone, hands-free cellular phone or wireless headset.

Check packet transmit (TxCnt) and packet receive (RxCnt) counters to verify that voice packets are flowing.


Note

Voice quality metrics do not account for noise or distortion, only frame loss.

Common Phone Status Messages

The following sections describe the common status messages that display on the phone screen.

Network Busy Message

Problem

The phone is unable to complete a call. The phone displays the Network Busy message.

Cause

The WLAN is not able to allocate bandwidth for the phone to complete the call.

Solution

Wait a few minutes and try the call again. If the problem persists, the WLAN might be congested. Consider increasing the WLAN bandwidth.

Leaving Service Area Message

Problem

The phone is unable to place or receive calls. The no signal icon displays on the phone screen. The phone displays the Leaving Service Area message.

Cause

The phone cannot detect any access point (AP) beacons

Solution

The phone is out of range of all APs.

  • Move to a location that is within the coverage area.

  • The AP has failed. Run diagnostic tests on the AP and replace if defective.

Locating Network Services Message

Problem

The phone is searching for an AP and the phone displays the Locating Network Services message.

Cause

The phone is searching all beacons and scanning for a channel and SSID to use.

Solution

Wait for the phone to complete the searching and scanning process. Depending on the signal strength of the available WLAN, this process can take a few minutes.

Authentication Failed Message

Problem

The phone is unable to access the WLAN, and the main phone screen is not active. The phone displays the Authentication Failed message.

Cause

The authentication server does not accept the security credentials.

Solution

Verify that the security mode and credentials are correct by viewing the Network profile. For information about accessing and changing Network profiles, see Access Network Profile Menu.

Configuring IP Message

Problem

The main phone screen is not active and the phone displays the Configuring IP message.

Cause

The phone is attempting to obtain network parameters such as its IP address, or the IP address of the gateway or router from the DHCP server.

Solution

Wait a few minutes for the phone to obtain the network parameters.

If the phone unable to retrieve the IP address, check that the DHCP server is up and running.

Configuring CM List Message

Problem

The main phone screen is not active and the phone displays the Configuring CM List message.

Cause

The phone is downloading its configuration files from the TFTP server.

Solution

Wait a few minutes for the phone to download all of its configuration files.

General Troubleshooting Information

The following table provides general troubleshooting information for the wireless IP phone.

Table 2. Cisco Unified Wireless IP Phone Troubleshooting Tips

Summary

Explanation

Phone is resetting

The phone resets when it loses contact with the Cisco Unified Communications Manager software. This lost connection can be due to any network connectivity disruption, including access point problems, switch outages, and switch reboots.

See Cisco Unified Wireless IP Phone Resets Unexpectedly.

Time on phone is incorrect

Sometimes the time or date on the phone is incorrect. The Cisco Unified Wireless IP Phone gets its time and date when it registers with Cisco Unified Communications Manager. Power cycle the phone to reset the time or date.

The time shows in either 12 hour or 24 hour format.

Phone firmware downgrades

After applying a Cisco Unified Communications Manager upgrade or patch, that is older than the current Cisco Unified Wireless IP Phone firmware, the phones could automatically downgrade to the load contained in the patch. Check the Cisco Unified Wireless IP Phone default image in the TFTP folder to fix this problem.

Battery life is shorter than specified

An unstable RF environment can cause the phone to remain in active mode because it is constantly seeking an AP. This reduces the battery life considerably. When leaving an area of coverage, shut down the phone.

Higher phone transmit power can affect battery life.

To maximize idle time on the phone and conserve battery life, you need to optimize the registration time so the phone can go into power save mode more often.

Phone call cannot be established

The phone does not have a DHCP IP address, is unable to register to Cisco Unified Communications Manager, and shows a Configuring IP or Registering message.

Verify the following:

  1. The Cisco Unified Communications Manager service is running on the Cisco Unified Communications Manager server.

  2. Both phones are registered to the same Cisco Unified Communications Manager.

  3. Audio server debug and capture logs are enabled for both phones. If needed, enable Java debug.

Call established with the iLBC protocol does not show that the iLBC codec is being used

Call statistics display does not show iLBC as the receiver/sender codec.

  1. Check the following using the Cisco Unified Communications Manager administration pages:

    • Both phones are in the iLBC device pool.

    • The iLBC device pool is configured with the iLBC region.

    • The iLBC region is configured with the iLBC codec.

  2. Capture a sniffer trace between the phone and Cisco Unified Communications Manager and verify that SCCP messages,OpenReceiveChannel, and StationMediaTransmit messages have media payload type value equal to 86. If so, the problem is with the phone; otherwise the problem is with the Cisco Unified Communications Manager configuration.

  3. Enable audio server debug and capture logs from both phones. If needed, enable Java debug.

For additional troubleshooting information, see the Cisco Unified Communications Manager Troubleshooting Guide.

Log Information for Troubleshooting

The following sections can help you gather troubleshooting information.

System Log Server

To gather information about problems with the wired network that can cause roaming delays or no connectivity, set up a system log server. Enable "syslog" on the network switches and access points that are logged to the system log server. Also enable Network Time Protocol (NTP) so that all access points and switches use the same times.

For information about setting up a system log server, see Set Up Trace Settings.

Phone Trace Logs

When you are experiencing problems registering with Cisco Unified Communications Manager, or call connections, you can use the Trace Logs function to trace the path of a packet from the phone to Cisco Unified Communications Manager. The result shows the number of hops and the IP address of each hop to reach the Cisco Unified Communications Manager server. You can use this information to check connectivity between the phone, Cisco Unified Communications Manager servers and gateways during a call.

To download trace logs, click Download Logs from the Trace Logs page.

Prevent Internet Explorer Error when Downloading Trace Logs

Depending on your settings, Internet Explorer might display an error when you download a trace log from the Trace Logs page.

To prevent this error from displaying, follow these steps.

Procedure
Step 1

From Internet Explorer, choose Tools > Internet Options.

Step 2

In the Internet Options window, click the Advanced tab.

Step 3

Under the Security section, enable Do not save encrypted pages to disk, and click OK.
Step 4

Exit all Internet Explorer sessions.

Reset Phone to Factory Defaults

You can clear all locally stored configuration options in a phone from the Phone Settings menu. When you use the restore to factory default option, all user-defined entries in Network Profiles, Phone Settings, and Call History are erased.

To erase the local configuration, follow these steps.

Procedure

Step 1

Choose SETTINGS > Phone Settings.

Step 2

Press **2 on the keypad.

The phone briefly displays Start factory reset now?

Step 3

Perform one of the following actions:

  • Press Yes to delete all settings. The phone cycles through normal startup procedures.

  • Press No to cancel the reset.

Step 4

Press SETTINGS > Network Profiles to reconfigure the network settings for your WLAN.

Caution 

Erasing the local configuration removes network profiles that are set up for the Cisco Unified Wireless IP Phone to access the WLAN. You must reconfigure the network settings after performing the reset to enable the phone to access the WLAN.

Troubleshooting Procedures

Use the procedures in this section to resolve problems.

Create New Configuration File


Note

When you remove a phone from the Cisco Unified Communications Manager database, its configuration file is deleted from the Cisco Unified Communications Manager TFTP server. The directory number (DN) remains in the Cisco Unified Communications Manager database as an unassigned DN. You can assign these DNs to other devices or delete them from the Cisco Unified Communications Manager database. You can use the Route Plan Report to view and delete unassigned reference numbers. See Cisco Unified Communications Manager Administration Guide for more information.

To create a new configuration file, follow these steps:

Procedure

Step 1

From Cisco Unified Communications Manager, select Device > Phone > Find to locate the phone that is not working properly.

Step 2

Choose Delete to remove the phone from the Cisco Unified Communications Manager database.

Step 3

Add the phone back to the Cisco Unified Communications Manager database. See Add Users to Cisco Unified Communications Manager for details.

Step 4

Power cycle the phone.

Verify DHCP Setup

To determine if the phone has been properly configured to use DHCP, follow these steps.

Procedure

Step 1

Verify that you have properly configured the phone to use DHCP. See DHCP Settings for details.

Step 2

Verify that the DHCP server has been set up properly.

Step 3

Verify the DHCP lease duration. Your local policy determines this setting.

Cisco Unified IP Phones send messages with request type 151 to renew their DHCP address leases. If the DHCP server expects messages with request type 150, the lease is denied, forcing the phone to restart and request a new IP address from the DHCP server.

Determine DNS or Connectivity Issues

To eliminate DNS or other connectivity errors, follow these steps.

Procedure

Step 1

Reset the phone to factory defaults. See Reset Phone to Factory Defaults for details.

Step 2

Modify DHCP and IP settings:

  1. Disable DHCP. See DHCP Settings for details.

  2. Assign static IP values to the phone. See DHCP Settings for details. Use the same default router setting used for other functioning Cisco Unified IP Phones.

  3. Assign a TFTP server. See Set Alternate TFTP Server for details. Use the same TFTP server used for other functioning Cisco Unified IP Phones.

Step 3

From Cisco Unified Communications Manager, choose System > Server and verify that the server is referred to by its IP address and not by its hostname.

Note 

Cisco recommends that you configure only IP addresses and not hostnames to eliminate the DNS resolution in the phone registration process.

Step 4

From Cisco Unified Communications Manager, select Device > Phone and verify that you have assigned the correct MAC address to this Cisco Unified IP Phone.

To determine the MAC address of a phone, see Device Information.

Step 5

Power cycle the phone.

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