Advanced Troubleshooting and Management of Mitel SX-200 ICP Using VxWorks Telnet and PRI Commands

The Mitel SX-200 Integrated Communications Platform (ICP) offers powerful tools for system management and troubleshooting through its VxWorks operating system. By accessing the system via Telnet on a specific port, technicians can perform a wide range of tasks from starting and stopping the embedded voicemail to conducting deep diagnostics on PRI (Primary Rate Interface) lines. This article will delve into how to use these tools effectively, providing detailed instructions and best practices.

1. Accessing VxWorks Shell via Telnet

To begin managing the SX-200 ICP system, you need to access the VxWorks shell. Unlike the default Telnet port (2000), advanced diagnostics and commands require access through a different port.

Connecting via Telnet:
Open your Telnet client and connect to the IP address of the SX-200 ICP using port 2002 instead of the standard 2000.
Log in using your usual credentials.
Upon successful login, you will see the message “shell restarted,” indicating that you are in the correct environment.

2. Common Commands in VxWorks Shell

Once logged in, you can utilize various commands to manage and troubleshoot the system. Here are some essential commands:

help: Lists available commands and their brief descriptions.
netHelp: Provides help on networking-related commands.
ioHelp: Offers assistance with input/output commands.

System and Network Commands:

devs: Lists all devices connected to the system.
iPVM_Status: Displays the status of the embedded voicemail system.
iPVM_Stop: Stops the embedded voicemail service.
iPVM_Start: Starts the embedded voicemail service.
ShowDspStatus: Displays the status of the Digital Signal Processors (DSPs).
ps: Shows all active processes and their runtime.
i: Lists all current tasks running on the system (Note: This command generates a large output).
arptabShow: Displays the ARP table, showing active IPs and MAC addresses on the local network.
ping “”: Performs a ping test to check network connectivity (Ensure to use quotation marks around the IP address).

System Configuration Commands:

bootChange: Allows editing of bootline parameters.
version: Displays the current bootline parameters.
relink_version: Shows if any software patches (relinks) have been applied to the system.
revs: Displays the boot ROM versions.
hardreset: Forces the system to reboot (similar to pressing the reset button on the controller).

FTP Management:

start_Ftpd: Starts the FTP server on the SX-200 ICP, allowing files to be uploaded or downloaded from the system.

3. Managing and Troubleshooting PRI Lines

The introduction of the embedded PRI module on the SX-200 ICP changed the way debug commands are executed. Traditionally, on an NSU (Network Services Unit) or PRI card, a technician would connect directly with a serial cable to input debug commands. On the SX-200 ICP, these commands are now inputted in CDE Form 43 and viewed via a secure Telnet session on port 2002.

Useful PRI Debug Commands:

pri chan state: Provides a snapshot view of the status of the PRI link, similar to the “option state” command on the NSU.
pri discall on: Enables detailed call information output, allowing technicians to see call information in both directions. This is similar to the “option +dispcall” command on the NSU.
pri discall off: Disables the detailed call information output.
pri cause on: Enables the display of cause codes, which help diagnose issues related to call failures.
pri cause off: Disables the display of cause codes.
tsp l2l3 on/off: Turns on or off the Layer 2/3 trace, which is typically only required when requested by Mitel for in-depth troubleshooting.

How to Use These Commands:

Access CDE Form 43:

Log into the installer level and navigate to CDE Form 43. Select the bay/slot corresponding to the PRI link you want to diagnose.
In the COMMENTS field, input the desired debug command.

View Output:

Secure Telnet to port 2002 to view the output of these commands. This will allow you to monitor the status and troubleshoot issues in real-time.

4. Understanding and Using PRI Cause Codes

PRI cause codes are critical for diagnosing and resolving issues related to PRI lines. These codes provide detailed reasons for call failures or disconnections, which can guide technicians in troubleshooting.

Common PRI Cause Codes:

Cause 1: Unallocated (unassigned) number. Indicates that the dialed number is not currently assigned.
Cause 3: No route to destination. Indicates that the network cannot route the call to the desired destination.
Cause 16: Normal call clearing. The call was terminated normally by one of the users.
Cause 17: User busy. The called party is unable to accept another call.
Cause 18: No user responding. The called party does not respond to the call setup request.
Cause 21: Call rejected. The network or remote device has rejected the call.

Using Cause Codes:

These cause codes can be used in conjunction with the pri cause on command to monitor and troubleshoot calls. Understanding these codes allows you to pinpoint issues such as incorrect configurations, network problems, or call routing issues.

5. Best Practices and Recommendations

Regular Monitoring: Regularly use the ps, iPVM_Status, and ShowDspStatus commands to monitor the health of the system.
Secure Connections: Always use secure Telnet (port 2002) when performing diagnostics to protect the system from unauthorized access.
Document Changes: Keep a detailed log of any changes made using the bootChange or other configuration commands to maintain system integrity.
Work with Mitel Support: For complex issues, particularly those involving Layer 2/3 traces or PRI cause codes, work closely with Mitel support to ensure accurate diagnostics and resolutions.

Conclusion

The VxWorks shell on the Mitel SX-200 ICP provides a robust environment for system management and troubleshooting. By using Telnet on port 2002, technicians can access powerful tools to manage embedded voicemail, PRI lines, and overall system performance. Understanding how to use these commands and interpret the results is essential for maintaining the reliability and efficiency of the SX-200 ICP in a production environment. Regular monitoring and thorough documentation will help prevent issues and ensure smooth operation.