Missing Previous day trend after roll out

[Edwardwale]

Some of my trends are missing previous day data after i did a roll out. What could possibly be the likely cause for this?

Can someone point me in the right direction to resolve this?

[olivier_vallee]

Hi @Edwardwale,

Can you give more detail about what you mean by rollout? Did you deploy a new version of your project using the Deployment feature? Or did you use backup/restore of the project on your Server node where the Trend Server (and other processes) are located?

Can you identify if it is just some Trend data that is missing or all Trend Data?

Next, identify how your Trend files are configured, paying close attention to the Filename. This basically tells the Trend Server where to store the trend history files (*.HST, *.001, *.002, etc).

Please note that by default, the amount of data is 2 days and will roll over as per the default schedule. See the help for details: https://docs.aveva.com/bundle/plant-scada/page/1217138.html

Let me know what you find and if I can be of further assistance

Kind regards

Olivier

[Edwardwale]

@olivier_vallee  Will the sampling period setting that is set to 1 and on Saturday to this? The old trends were cleared on Saturday 02/11/2024 and so we could not go back to see the trends before that.

[olivier_vallee]

So you need to start with your requirements. How long do you require the Trend history to remain? If for example you want at a minimum, 7 days of Trend data, then you would require the following settings:
No. File: 8

Period: 24 hours

Time: 00:00:00 (this time is specified in UTC and defines when the history file is created)

In plain English, what this means is there will be at least 7 files (while the 8th is first created), each storing 24 hours worth of Trend data, with file roll over time at Midnight UTC.

This help section also explains how history files work:

https://docs.aveva.com/bundle/plant-scada/page/1217144.html

I hope this information helps you.

Kind regards

Olivier