---
title: Multi tier historian deployment
slug: concepts/multi-tier-historian-deployment
docTags: fRI3KpfLObYoXM9W4ao1n
createdAt: 2025-08-31T16:37:02.921Z
---

In a multi tier historian deployment, each site has its own historian instance for local collection and access (tier 1), while selected data is forwarded to a central historian (tier 2).

This architecture can be extended with an arbitrary number of 'tiers'. At each tier, data is aggregated, potentially enriched and subsequently forwarded to the next tier.

See [Tiering vs replication](docId\:feifArGIpyN0BarQuv0Hk) for how the two differ.

## When it’s used

- Uninterrupted local access to historian data is critical
- Local data ownership and governance is important
- Short-term, high-resolution data lives on-premise, while long-term, typically lower-resolution, data is stored centrally
- For secure access from the business or enterprise network to data from a historian in a high security OT network

## Architecture

- Collectors feed data into a local historian at each site
- Local historians store historical data (short- or medium-term)
- Local historians forward all or a subset of the data to the central historian

:::hint{type="info"}
Factry Historian uses out-of-the-box connectivity through open standards. Therefore, there is not one, but there are multiple ways to implement this historian-to-historian communication.
:::

- The central historian runs in the cloud or on one of the production sites

::Image[]{src="https://app.archbee.com/api/optimize/SMPo4IS9FkillUAMsur2c/RyPKE03yZUm3PrRVD-RH9-20250925-085927.png" size="40" width="1527" height="2619" position="center" caption="Multi tier architecture" darkWidth="1527" darkHeight="2619" showCaption="true"}

## Functions used

- Push strategy: [Forwarders](docId\:TD6EMj3F_0XsGJI7p4dAg) can be used to control what data is shared with the central historian

## Benefits

- Continuous local access to dashboards and data, even during outages
- Centralized reporting and enterprise integration still possible
- Flexibility to forward only relevant data

## Considerations

- More servers and datasets to manage across sites
- Local IT/OT support required to maintain historian instances
- Data duplication across local and central historians
- Extra load on local historians
- Data governance processes needed to maintain central truth
- Dashboards/configurations are harder to share between sites

## Summary

A more complex version of hub-and-spoke: data is collected and stored locally, then aggregated in the next tier. Useful when local data access and ownership is crucial.