Security Onion VM Not Picking Up Traffic Mirrored from Netgear Switch Ports
In this article, we will discuss how to properly configure a Netgear switch to mirror traffic to a Security Onion VM running on a PC with two network interface cards (NICs). We will cover the key concepts and configurations needed to ensure that the Security Onion VM is receiving the mirrored traffic from the Netgear switch.
Prerequisites
- A PC with two NICs
- A Netgear switch with at least four ports
- Security Onion VM installed on the PC
Configuring the Netgear Switch
The first step is to configure the Netgear switch to mirror traffic from two ports to another port that is connected to the Security Onion VM. In this example, we will be using ports 3 and 4 as the source ports and port 7 as the destination port.
To configure the switch, follow these steps:
- Connect to the switch using a web browser.
- Navigate to the
Monitoringsection and click onPort Mirroring. - Select
Enable Port Mirroring. - In the
Source Portsfield, enter3,4. - In the
Destination Portfield, enter7. - Click
Applyto save the changes.
Configuring the Security Onion VM
The next step is to configure the Security Onion VM to receive the mirrored traffic from the Netgear switch. In this example, we will be using the second NIC in the PC as the interface that is connected to the Netgear switch.
To configure the Security Onion VM, follow these steps:
- Start the Security Onion VM.
- Open a terminal window and enter the following command to check the status of the NICs:
ifconfigThis will display a list of the NICs and their current status.
- Identify the NIC that is connected to the Netgear switch.
- Enter the following command to configure the NIC to receive mirrored traffic:
sudo nano /etc/network/interfacesThis will open the interfaces file in a text editor.
- Add the following lines to the file:
auto :1
iface :1 inet manual
up ifconfig :1 up
up ip link set :1 promisc on
down ip link set :1 promisc off
down ifconfig :1 down Replace
- Save the changes and exit the text editor.
- Enter the following command to restart the networking service:
sudo service networking restartTesting the Configuration
To test the configuration, generate some traffic on the source ports (3 and 4) and check if the Security Onion VM is receiving the mirrored traffic on the destination port (7).
References
- Netgear Switch Port Mirroring: https://kb.netgear.com/31427/How-do-I-set-up-Port-Mirroring-on-my-managed-switch
- Security Onion VM: https://securityonion.net/
In this article, we discussed how to configure a Netgear switch to mirror traffic from two ports to another port that is connected to a Security Onion VM. We covered the key concepts and configurations needed to ensure that the Security Onion VM is receiving the mirrored traffic from the Netgear switch. By following the steps outlined in this article, you should be able to properly configure your Netgear switch and Security Onion VM to monitor the traffic on your network.