DataPower produces a set of metrics every few minutes to assist DataPower administrators to monitor the health of the DataPower. These metrics are known as DPmon (DataPower Monitoring) statistics and DPmon is a good starting point for any administrator wanting to monitor their DataPower devices.

What is DPmon?
DPmon is a file on the DataPower device that stores nmon data, which provides detailed system performance metrics like CPU usage, memory, and network activity, allowing for performance analysis and troubleshooting. Administrators can extract the dpmon files from the gateway's temporary storage (usually at temporary:///dpmon/dpmon) and then load it into an nmon visualizer tool to visualize the collected data and gain insights into the gateway's health and resource utilization.

• Purpose: DPmon is a DataPower-specific file that captures nmon (Network Monitor) performance data from the DataPower gateway.
• Content: It contains detailed information about the gateway's performance, including CPU usage, memory consumption, disk I/O, and network statistics.
• Function: By collecting and storing this performance data, DPmon helps administrators monitor the gateway's health, identify resource bottlenecks, and optimize its performance over time.

Why is DPmon important? 

• Troubleshooting: DPmon provides near-real-time visibility into gateway performance and resource utilization, which significantly speeds up problem determination and troubleshooting efforts.
• Performance optimization: By analyzing the performance metrics in DPmon, administrators can identify areas where the gateway might be under stress and make adjustments to improve efficiency.
• Capacity planning: The trending analysis from DPmon data helps in forecasting future resource needs in order to prevent DataPower servers being overloaded due to excessive CPU and memory use, before they impact service delivery.

How to use DPmon:

• Access the file: You can access the dpmon files on the DataPower appliance, typically located in the temporary directory at temporary:///dpmon/dpmon.
• Download the file: Use the command line interface (CLI) or the management interface to download this file from the appliance to your local machine.
• Visualise the data: Load the downloaded dpmon file into an nmon visualiser tool, such as NMONVisualizer. Chris Phillips has a blog about this: https://chrisphillips-cminion.github.io/apiconnect/2021/05/17/datapower-nmon.html but I will describe the use of NMONVisualizer in this blog.
• Analyse performance: The visualiser will then display the nmon data in an easily understandable format, allowing you to analyze trends and identify performance issues.

Step-by-step process:

1. Find and download the dpmon files in the DataPower webGUI as follows:
   - go to File Management in the DataPower webGUI, under the temporary folder:
   
   
   Click on the 3-dits icon and download dpmon.1-8:
   
   
2. Download the NMONVisualizer tool: go to the NMONVisualizer Homepage ( https://nmonvisualizer.github.io/nmonvisualizer ) and download the *.jar file from the Releases page ( https://github.com/nmonvisualizer/nmonvisualizer/releases ).
3. Rename each of the dpmon files download to have a .nmon suffix - this is to enable NMONVisualizer to process them.
4. Run the NMONVisualizer tool against the dpmon*.nmon files as follows:
   - move the dpmon files into a subdirectory called dpmons.
   - run this on the command line: $ java -jar NMONVisualizer_2025-01-01.jar com.ibm.nmon.ReportGenerator dpmons
   - screen output is something like this:
   Charting interval All Data: 14:21:55 Sep 01 - 14:37:05 Sep 01
   Writing charts to /dpmon-for-blog/dpmons/charts
       Creating summary charts .......... Complete (10/10)
       Creating charts for datapower-for-apic-01 ................... Complete (19/19)
   Charts complete!
   - go to the dpmons subdirectory where a charts directory has been created with sets of charts based on the dpmon files processed by NMONVisualizer.
   
   
5. You can now view the DPmon charts - examples:
   
   
   
   
   
   

Next Steps:

• DataPower should have DPmon activated by default, if not then you can set it up on your DataPower devices - the dpmon files are stored under the Default Domain under File Management – temporary – dpmon. These files will rollover every 15 minutes, overwriting after the ninth file fills up so around 2 hours of data is stored at any one time and they can be manually downloaded via the webGUI or extracted from File Management with a script ( IBM Support have provided a the script: https://www.ibm.com/support/pages/system/files/support/swg/swgtech.nsf/0/89995b90dcdfe12985257552005e6fa2/$FILE/sample_cli_script.sh ).
• Additionally there are various Support pages containing details on how to setup and re-configure DPmon should this be required:
  https://www.ibm.com/support/pages/mustgather-ibm-datapower-gateway-appliance-statistics-gathering
  https://www.ibm.com/support/pages/mustgather-memory-growth-datapower-firmware
• For a more comprehensive DataPower monitoring, tracing and management tool, IBM offer DataPower Operations Dashboard (DPOD). Here are the IBM Documentation pages for DPOD: https://montier.atlassian.net/wiki/spaces/DpodDocumentation/pages/15910731874/Product+Info