DU-Moniter

Real-Time Sync Log Monitor

Overview

This repository contains two Python scripts used for PTP synchronization monitoring and resynchronization time testing with a commercial RU (Benetel) device connected at IP address 10.10.0.100.

Both scripts connect via SSH to the RU, monitor /var/log/pcm4l, and either visualize synchronization metrics in real-time or record recovery time under different configuration settings.

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1. du_monitor.py

Purpose

Continuously monitor and visualize synchronization performance metrics (offset, delay, mean, std) in real time from the Benetel RU via SSH.

Connection Target

• RU IP: 10.10.0.100
• Log Source: /var/log/pcm4l

Output

• Saves all parsed data to a CSV file named sync_log.csv.
• Displays four live-updating plots:
  • Offset (ns)
  • Delay (ns)
  • Mean (ns)
  • Standard Deviation (ns)

How It Works

1. Opens an SSH connection and runs:

   ssh root@10.10.0.100 tail -F /var/log/pcm4l

2. Parses log lines containing either:

   offset: X ns delay: Y ns
   

   or

   mean: M ns, std: S ns
   

3. Writes parsed values with timestamps into sync_log.csv.
4. Plots real-time trends using matplotlib.

Usage

python3 du_monitor.py

Requirements

• Python 3.7+
• Installed libraries:

  pip install matplotlib

Output Example (Terminal)

[RECV] offset=-12.3 ns, delay=184.0 ns
[RECV] mean=0.2 ns, std=0.8 ns

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2. sync_test.py

Purpose

Automatically test re-synchronization time after simulated sync loss, across different logSyncInterval values.

Connection Target

• RU IP: 10.10.0.100
• Log Source: /var/log/pcm4l

Configuration Paths

• PTP_CONF = /home/inss/srs_scripts/ptp4l.conf
• SCRIPT = /home/inss/srs_scripts/s0_ptp_run.sh
• Output results saved to:

  /home/inss/peihao/resync_times.csv
  

How It Works

1. Iterates through a list of logSyncInterval values: [-5, -4, -3, -2, -1, 0, 1, 2].
2. For each interval:
   • Updates the logSyncInterval in ptp4l.conf.
   • Restarts the PTP service via s0_ptp_run.sh.
   • Monitors /var/log/pcm4l remotely through SSH.
3. Detects sync loss (Lost master alarm raised) and recovery (offset: / delay:).
4. Calculates and logs the resynchronization duration for each interval.
5. Saves all results into resync_times.csv.

Usage

python3 sync_test.py

Requirements

• Python 3.7+
• SSH access to the RU at 10.10.0.100
• Local read/write permission for the paths defined above

Output Example (Terminal)

[INFO] logSyncInterval set to -3
[INFO] Restarting PTP service...
[LOG] Lost master detected
[LOG] Recovered sync in 5.62 seconds
[DONE] Results saved to /home/inss/peihao/resync_times.csv

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Notes

• Both scripts assume passwordless SSH access to root@10.10.0.100. You can enable this using an SSH key:

  ssh-copy-id root@10.10.0.100

• Ensure /var/log/pcm4l is being continuously written by the RU’s synchronization process.
• The scripts are designed for Benetel commercial RU, but can be adapted for other devices by changing the SSH target and log parsing regex.