> For the complete documentation index, see [llms.txt](https://docs.nuvolos.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.nuvolos.com/reference/configuration/distribution-strategies.md).

# Distribution Strategies

When distributing objects between Instances, you choose a distribution strategy that determines how the target handles conflicts with existing content. The strategy is selected per object type (files, applications, tables) during the distribution flow.

### Overwrite

This is the default strategy. If a file with the same name and path already exists in the target, it will be overwritten by the distributed file. Files that do not exist in the target will be created. This strategy corresponds to the `OVERWRITE` mode in the backend.

{% hint style="info" %}
Overwrite is the default because it gives the distributor control over the target without unintended side effects. We recommend this setting for most use cases.
{% endhint %}

### Distribute Extra (Ignore Existing)

This is the least intrusive strategy. If a file with the same name and path already exists in the target, it will **not** be overwritten. Only files that do not already exist in the target will be created. This strategy corresponds to the `IGNORE_EXISTING` mode in the backend.

{% hint style="warning" %}
This strategy is useful if you do not want to accidentally modify existing files in the target.
{% endhint %}

### Mirror (Clear Target and Replace)

This is the most intrusive strategy. It first erases the contents of the target area (e.g., `/files`, `/home`, `/apps`) completely and then copies the distributed objects into it. This ensures the target is an exact replica of the source. This strategy corresponds to the `MIRROR` mode in the backend.

{% hint style="info" %}
"Mirror" is most useful when you want to guarantee that the target environment runs exactly as your source environment.
{% endhint %}

### Skip

This strategy performs no action. The distribution for the specified object type (e.g., files, applications) is skipped entirely. This is useful in automated or conditional distribution scenarios where you may want to exclude certain object types from the process. This strategy corresponds to the `SKIP` mode in the backend.

### Strategy summary

|                  |                  |                              |                         |
| ---------------- | ---------------- | ---------------------------- | ----------------------- |
| **Strategy**     | **Backend mode** | **Existing files in target** | **New files in target** |
| Overwrite        | OVERWRITE        | Replaced                     | Created                 |
| Distribute Extra | IGNORE\_EXISTING | Preserved                    | Created                 |
| Mirror           | MIRROR           | Erased before copy           | Created                 |
| Skip             | SKIP             | No action                    | No action               |
