VIRL ASAv with ASDM

April 16, 2018 at 6:10 pm

VIRL

I had many requests to demonstrate how to use the ASDM GUI to manage an ASAv running inside of VIRL. Here is the video demonstration of how to do it. Enjoy!

Basic Setup of the ASAv in EVE-NG

April 11, 2018 at 8:09 pm

ASAv

In this video, we will examine the configuration of the ASAv for basic practice that would be appropriate for training such as CCNA Security.

An Example of a Security Exploit Due to the Native VLAN

January 18, 2018 at 8:24 pm

Native VLAN

In many of our Cisco courses, we learn that networking best practices often point to the non-use of the Native VLAN. But why is this?

It turns out there are security vulnerabilities that could result from having a VLAN not tagged across your trunk links. For example, there is the VLAN hopping attack.

Here is how this attack could work:

Step 1: A bad person at a customer site wants to send frames into a VLAN that they are not part of.

Step 2: This person double tags the frame (Q-in-Q) with the outer frame matching the native VLAN in use at the provider edge switch.

Step 3: The provider edge switch strips off the outer tag (because it matches the native VLAN), and send this frame across the trunk.

Step 4: The next switch in the path examines the frame and reads the inner VLAN tag and forwards the frame accordingly.

Notice this attack is unidirectional. The attacker can send traffic into the VLAN, but traffic will not return. Even still, this is obviously not something we want taking place.

What are possible solutions?

  • Use ISL trunks in the cloud – this becomes less and less possible as ISL trunks fade away.
  • Use a Native VLAN that is outside of the range permitted for the customer.
  • Tag the native VLAN in the cloud.

 

Static Routes on the ASA

September 24, 2014 at 9:00 am

In this MicroNugget, I demonstrate the configuration and verification of static IP routes on the Cisco ASA firewall. This tutorial relates to CBT Nuggets’ CCNA Security certification playlist. Try CBT Nuggets free for 7 days.

MicroNugget: ASA Interface Setup and Security Levels

September 22, 2014 at 9:00 am

I demonstrate the initial setup of ASA interfaces and also teach about security levels in the ASA. This tutorial relates to CBT Nuggets’ CCNA Security training. Try CBT  Nuggets free for 7 days.

MicroNugget: The ASA in GNS3

September 20, 2014 at 9:00 am

In this MicroNugget, I demonstrate the setup and testing of an ASA in GNS3 version 0.8.7. This tutorial relates to CBT Nuggets’ CCNA Security training. Try CBT Nuggets free for 7 days.

MicroNugget: The ASA Setup Wizard

September 19, 2014 at 9:00 am

I demonstrate the setup script on the Cisco ASA firewall. This tutorial relates to CBT Nuggets’ CCNA Security training. Try CBT Nuggets free for 7 days.