> For the complete documentation index, see [llms.txt](https://help.glpi-project.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.glpi-project.org/tutorials/inventory/advanced-usage/using-blacklist.md).

# Using blacklist

{% hint style="danger" %}
**This is for advanced use only**
{% endhint %}

The blacklist identifies the information that will not be retrieved when a PC is inventoried or when users are synchronised.

It is possible to prohibit a certain amount of information, such as IP addresses in 0.0.0.0 or a user with an @yopmail.com email address.

{% hint style="success" %}
You can blacklist the following items:

* IP
* MAC
* Serial number
* UUID
* Email (for users)
* Model
* Manufacturer
* Manufacturer
  {% endhint %}

## Add a new blaclist

For our example, we will block IPv6 forwarding

* To configure a blacklist, go to **`Setup`** > **`Dropdowns`** > **`Blacklists`**
* Click on **`+ADD`**
* Name your new blacklist
* Indicate the value (**`::1`** for IPv6)
* Select the expected value (IP for our example)

<figure><img src="/files/I2eqD5vghAfInWR5DEKP" alt=""><figcaption><p>View of blacklist</p></figcaption></figure>

## Delete a Blacklist

* To delete a blacklist, click on **`Delete permanently`**

<figure><img src="/files/mwYG7UBtOfMAE5k4jD0S" alt=""><figcaption><p>Delete a blacklist</p></figcaption></figure>

* You can use massive action to delete one or more blaclists

<figure><img src="/files/fB5cRXutC2eUJQm4Xpcr" alt=""><figcaption></figcaption></figure>


---

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