> ## Documentation Index
> Fetch the complete documentation index at: https://docs.onebucket.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Placement by policy

> Each bucket lives where the rule says, under your own keys

## The situation

A regulated or multinational business must keep certain data in a given region or cloud, under its own keys, while the rest of the business runs on a global platform. Today that means separate buckets, separate pipelines and a compliance review per application.

## What OneBucket changes

The rule is written once, at the layer, per bucket. A sovereign bucket is mapped to EU backends under your keys; the global bucket goes wherever policy says. Replication adds copies where they are required. Applications and agents still use one endpoint, and backend keys stay with you.

![One global application writes through OneBucket; placement policy sends eu-customers to an EU region under customer keys and global-data to a US region, with an on-prem replica](https://mintcdn.com/onebucket/IRmZGtHTOOl3yo0n/images/scenarios/placement.png?fit=max\&auto=format\&n=IRmZGtHTOOl3yo0n\&q=85\&s=d8dc9a0b4d0315dbd885bd4f59e4eb59)

## How it works

* **Per-bucket placement.** A policy maps a OneBucket to its backends and its replication targets. Placement is set per bucket, not per object: objects are not routed individually by prefix or tag.
* **Keys stay with you.** Each backend is registered with its own credentials, held in the secure vault. Customer-managed keys remain customer-managed.
* **Proof of location.** The `locate` tool returns where any object physically lives, which is what an auditor wants to see.
* **Regions.** OneBucket runs clusters in multiple regions. Global hostnames route each request to the nearest cluster; pin a cluster when requests must land in one place.

## Related

* [Set up your OneBucket](https://docs.onebucket.io/setup.md)
* [Write once, land in several clouds](https://docs.onebucket.io/scenarios/replication.md)
* [Migrate behind a fixed endpoint](https://docs.onebucket.io/scenarios/migration.md) when the move is a cloud exit for sovereignty reasons


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