> For the complete documentation index, see [llms.txt](https://docs.ionos.com/cloud/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ionos.com/cloud/network-services/vdc-networking/firewall.md).

# NIC-based Firewall

IONOS CLOUD NIC-based Firewall: manage NIC-level firewall rules for VDC resources

Activate and configure a [<mark style="color:blue;">Firewall</mark>](https://docs.ionos.com/cloud/support/general-information/glossary-of-terms#firewall) for each Network Interface Card ([<mark style="color:blue;">NIC</mark>](https://docs.ionos.com/cloud/support/general-information/glossary-of-terms#nic)) to better protect your servers from attacks. <code class="expression">space.vars.ionos\_cloud</code> Firewalls can filter incoming (ingress), outgoing (egress), or bidirectional traffic. When configuring firewalls, define appropriate rules to filter traffic accordingly.

{% hint style="info" %}
**Note:** We recommend using [<mark style="color:blue;">Network Security Groups (NSGs)</mark>](/cloud/security/network-security-groups.md) for centralized and fine-grained firewall management in Virtual Data Centers (VDCs). It will enable you to control and monitor your network traffic efficiently.
{% endhint %}

## Quick Links

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-target data-type="content-ref"></th></tr></thead><tbody><tr><td><mark style="color:blue;"><strong>How-Tos</strong></mark></td><td>Learn how to enable and manage firewall protection on your NICs to filter incoming, outgoing, or bidirectional traffic.</td><td><a href="/cloud/network-services/vdc-networking/firewall/how-tos.md">How-Tos</a></td></tr></tbody></table>


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