> For the complete documentation index, see [llms.txt](https://kchuene.gitbook.io/data-communication-project/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://kchuene.gitbook.io/data-communication-project/archive/ossec-agent.md).

# OSSEC Agent

OSSEC Agent for Host Intrusion Detection, reporting back to the OSSEC server.

## Pre-Install

**Add source**

{% code overflow="wrap" lineNumbers="true" %}

```
wget -q -0 - https://update.atomicorp.com/installers/atomic | sudo bash
```

{% endcode %}

**Update**

{% code overflow="wrap" lineNumbers="true" %}

```
sudo apt update
```

{% endcode %}

{% hint style="info" %}
Head to the **Ubuntu** tab on the OSSEC download page linked below for this specific reference.
{% endhint %}

## Agent Installation

**Install directly on the host OS**

{% code overflow="wrap" lineNumbers="true" %}

```
sudo apt install ossec-hids-agent
```

{% endcode %}

## Server Authentication

**Authenticating the agent to the OSSEC server**

Having a key distribution service up on the server, i.e. setup with `ossec-authd` , connect to the server with `agent-auth` to receive and install the agent key for authentication.

{% code overflow="wrap" lineNumbers="true" %}

```
/var/ossec/bin/agent-auth -m 192.168.56.1 -p 1515 -A production
```

{% endcode %}

{% hint style="info" %}
The **-m** option specifies the server IP, and the **-p** option the port of the key distribution service, i.e. `ossec-authd` 
{% endhint %}

**Check Server IP in config**

Make sure the agent will attempt to connect to the right IP in future, edit `/var/ossec/etc/ossec.conf` 

{% code overflow="wrap" lineNumbers="true" %}

```
<client>
   <server>192.168.56.1</server>
</client>
```

{% endcode %}

and restart the service

{% code overflow="wrap" lineNumbers="true" %}

```
sudo systemctl restart ossec
```

{% endcode %}

{% embed url="<https://www.ossec.net/download-ossec/>" %}

{% embed url="<https://www.ossec.net/docs/docs/manual/agent/agent-auth.html>" %}


---

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