{"id":1663,"date":"2023-08-01T19:43:59","date_gmt":"2023-08-01T18:43:59","guid":{"rendered":"https:\/\/thomas-kopton.de\/vblog\/?p=1663"},"modified":"2023-08-01T19:48:22","modified_gmt":"2023-08-01T18:48:22","slug":"multiple-metrics-with-aria-operations-telegraf-custom-scripts","status":"publish","type":"post","link":"https:\/\/thomas-kopton.de\/vblog\/?p=1663","title":{"rendered":"Multiple Metrics with Aria Operations Telegraf Custom Scripts"},"content":{"rendered":"\n

When using VMware Aria Operations<\/mark>, integrating telegraf<\/mark> can significantly enhance your monitoring capabilities, provide more extensive and customizable data collection, and help ensure the performance, availability, and efficiency of your infrastructure and applications.<\/p>\n\n\n\n

Utilizing the telegraf agent you can run custom scripts in the end point VM and collect custom data which can then be consumed as a metric.<\/p>\n\n\n\n

One very important constraint is that the script has to delivery exactly one int64 value.<\/mark><\/p>\n\n\n\n

Problem Statement<\/h5>\n\n\n\n

If you need to return multiple values or even multiple decimals or floating point values you will need to have multiple scripts for every single value and encode and decode any decimals or floating point metrics.<\/p>\n\n\n\n

Even if configuring and running multiple scripts is a doable approach sometimes you have one script providing multiple metrics and breaking down such single script into multiple ones is not an option.<\/p>\n\n\n\n

Challenge now is: how to put the multiple metrics into one value and how to revert this one value back into multiple metrics<\/mark>. Basically an encode – decode problem statement<\/mark>.<\/p>\n\n\n\n

Solution<\/h5>\n\n\n\n

Let’s start with some basics in math and recall how the decimal system<\/strong> works. For this I will refresh your memories deconstructing a large number into small pieces – 420230133702600<\/strong>. The following picture shows how this number looks like in the decimal system. I have truncated the sum expression for visibility but you get the point, the number is the sum of it positional values multiplied with the corresponding power of 10.<\/p>\n\n\n\n

\"\"<\/a><\/figure>\n\n\n\n

The idea now is very simple. I will encode two values (in my working use case I use two but it works for any number as long as inn the end it fits into int64<\/strong>) into a larger number using the positions within this single number as displayed in the next picture for four independent values: 7, 62, 230, 4200<\/code> which will give es one number – 7622304200<\/code>.<\/p>\n\n\n\n

\"\"<\/a>
Figure 02: Encoding four numbers into one number.<\/em><\/figcaption><\/figure>\n\n\n\n
So how to do that encoding mathematically?<\/h6>\n\n\n\n

Depending on the length of the single numbers we need to determine the power of 10 at the position where this single number should start within the final value. 4200 starts at 10^0, 230 at 10^4, 62 at 10^7 and 7 at 10^9. The sum is our single value:<\/p>\n\n\n\n

4200 * 10^0 + \n230  * 10^4 +\n62   * 10^7 +\n7    * 10^9 = 4.200 + 2.300.000 + 620.000.000 + 7.000.000.000 = 7622304200<\/code><\/pre>\n\n\n\n
And now, how to decode that number back into single values?<\/h6>\n\n\n\n
What we have now is one large number with encoded four values, n1, n2, n3, n4<\/code>.<\/p>\n\n\n\n
\"\"<\/a>
Figure 03: Encoding four numbers into one number and the resulting sum.<\/em><\/figcaption><\/figure>\n\n\n\n
The math goes backwards this time, and we need two additional mathematical expressions:<\/p>\n\n\n\n