> For the complete documentation index, see [llms.txt](https://documentation.ocsinventory-ng.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://documentation.ocsinventory-ng.org/project-overview/v2-vs-v3-whats-changed.md).

# v2 vs v3: What’s changed?

If you’re planning an upgrade, please read through the [Migration guidelines](/project-overview/migration-guide.md) and [Agent overview](/administrator-docs/agent-setup/agent-overview.md).

### Technology

Perl and PHP, which were the main languages used by the 2.x version, have been retired. The 3.x version uses a more modern stack:

* **Backend**: Python **Django** + **Django REST Framework**
* **Frontend**: **Vue.js** web console

### Architecture

{% columns %}
{% column %}
In 2.x:

* the **communication server** wrote inventories to the database
* the **web console** reads and wrote the database directly
  {% endcolumn %}

{% column %}
In 3.x:

* the **backend API** is the single entry point
* the **agent** sends inventory data to the API
* the **web console** calls the same API
  {% endcolumn %}
  {% endcolumns %}

For the diagram version of this comparison, see **Reference architectures** in [Migration guidelines](/project-overview/migration-guide.md).

### Agent (client)

{% columns %}
{% column %}
In 2.x:

* unix-like agents were **Perl** based
* the Windows agent was mainly **C++** based
  {% endcolumn %}

{% column %}
In 3.x:

* the agent is a **single cross-platform codebase** written in **Dart**
* the agent focuses on **inventory collection** only
  {% endcolumn %}
  {% endcolumns %}

### Network discovery

{% columns %}
{% column %}
In 2.x:

* agents would run **SNMP** scans
* agents would run **IPDiscover** scans
* SNMP inventory was kept separate from standard inventories
  {% endcolumn %}

{% column %}
In 3.x:

* **SNMP Scanner** is a dedicated standalone tool
* SNMP inventories are stored along standard inventories
* **IPDiscover** runs on the server only
  {% endcolumn %}
  {% endcolumns %}

{% hint style="warning" %}
If you relied on agent-side SNMP or IPDiscover in 2.x, validate the 3.x equivalents (see [Network Discovery](/administrator-docs/network-discovery.md)).
{% endhint %}

### Plugins/extensions

The new [Template](/user-docs/asset-management/inventory-and-templates.md#template-inventory) system introduced in 3.x makes many of the old plugins/extensions obsolete due to its highly customizable nature : extensions that were used solely to retrieve additional data from agents can now be replaced by creating a custom template.

3.x extensions will instead focus on extending the functionality of the web console itself or sourcing external data.

### Features

Some features were reworked, replaced, or are still in progress:

* **Registry** data can now be collected through the creation and use of custom [Templates](/user-docs/asset-management/inventory-and-templates.md#template-inventory).
* **Local import / Perl injector** are replaced by the local JSON workflow. The agent can generate JSON in [local mode](/administrator-docs/agent-setup/configuration.md#execution-modes), and you can post it directly to the API. Assets can also be created manually this way.
* **Software categories** will be coming soon and rely on the [Rules engine](/administrator-docs/server-setup/configuration/advanced/managing-rules.md).
* **CVE** inventory is planned to be reworked and consolidated to offer a better experience.
* **Notifications** are planned.
* **Green IT** is planned.

New features introduced in 3.x:

* [**Rules engine**](/administrator-docs/server-setup/configuration/advanced/managing-rules.md)
* [**Automated actions**](/administrator-docs/server-setup/configuration/advanced/automations.md)
* [**Inventory logs**](/administrator-docs/server-setup/configuration/advanced/inventory-logs.md)


---

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