First Published: June 1, 2023

Introduction

This document explains how to deploy the Threat Defense Virtual auto scale solution using GWLB on AWS to inspect north-south traffic

How to Set Up the Threat Defense Virtual Auto Scale Solution using GWLB on AWS to Inspect North-South Traffic

The auto scale solution enables the deployment, scaling, and management of a group of Threat Defense Virtual instances that are hosted for traffic inspection. The traffic is distributed across single or multiple Threat Defense Virtual instances depending on performance or usage capacity.

The GWLB acts as a single entry and exit point to manage internally and externally generated traffic and scales up or down the number of Threat Defense Virtual instances in real time based on traffic load.


Note

The parameter values used in this use case are sample values. Change these values as per your requirement.

Sample Topology

This sample topology illustrates how inbound and outbound network traffic flow is distributed to Threat Defense Virtual instances through the GWLB and then routed to the application VPC and back.

Figure 1. Threat Defense Virtual Auto Scale Solution with GWLB

Inbound Traffic Inspection


The Internet Gateway (IGW) receives traffic from the Internet.


Traffic is routed to the Gateway Load Balancer endpoint (GWLBe) as per the routes in the Ingress Route Table.



The GWLBe is attached to the endpoint service in the Security Virtual Private Cloud (VPC). The GWLB encapsulates the received traffic and forwards it to the Threat Defense Virtual auto scaling group for inspection.



The traffic inspected by the auto scaling group is returned to the GWLB and then to the GWLB endpoint.


The GWLB endpoint forwards the traffic to the Application VPC from where it is routed to the resources in the Application subnet.

Outbound Traffic Inspection


Traffic from the Application subnet resources is routed to the GWLBe in the same VPC.


The GWLBe is attached to the endpoint service in the Security VPC. The GWLB encapsulates the received traffic and forwards the same to the auto scaling group for inspection.



The traffic inspected by the auto scaling group is returned to the GWLB and then to the GWLBe.


After the traffic arrives in the origin VPC, it is forwarded to the IGW as per the routes defined in the Egress Subnet Route Table.



The IGW sends the traffic to the Internet.

End-to-End Procedure

The following flowchart illustrates the workflow for deploying Threat Defense Virtual auto scale solution with GWLB on Amazon Web Services (AWS).

Workspace

Steps

Local Host

Download the required files from GitHub

Amazon CloudFormation Console

Customize and Deploy Infrastructure Template

Management Center

Configure Network Infrastructure

Local Host

Update the Configuration.json file

Local Host

Configure Infrastructure Components using AWS CLI

Local Host

Create Target Folder

Local Host

Upload Files to Amazon S3 Bucket

Amazon CloudFormation Console

Deploy the Auto Scale Solution

Amazon EC2 Console

Edit Auto Scale Group

Amazon VPC Console

Create the GWLB Endpoint

Amazon VPC Console

Configure Routing for VPC

Prerequisites

  • Download the lambda-python-files folder from GitHub. This folder contains the following files:

    • Python (.py) files that are used to create the lambda layer.

    • A configuration.json file that is used to add static routes and customize any network parameters, as required.

  • Download the following CloudFormation templates from GitHub:

    • infrastructure_gwlb.yaml – Used to customize the components in the AWS environment.

    • deploy_ngfw_autoscale_with_gwlb.yaml – Used to deploy the AWS Auto Scale with GWLB solution.

  • [Optional] Collect values for the template parameters, wherever possible. This will make it easier to enter the values quickly while deploying the templates on the AWS Management console.

Amazon CloudFormation console – Customize and Deploy the Infrastructure Template

Perform the steps given in this section to customize and deploy the infrastructure template.

Procedure

Step 1

On the AWS Management console, go to Services > Management and Governance > CloudFormation, and click Create stack > With new resources(standard).

Step 2

Choose Upload a template file, click Choose file, and select infrastructure_gwlb.yaml from the folder in which you downloaded the files.

Step 3

Click Next

Step 4

On the Specify stack details page, enter a name for the stack.

Step 5

Provide values for the input parameters in the infrastructure_gwlb.yaml template.

Parameters

Values

Pod Configuration

  

Pod Name

infrastructure

Pod Number

1

S3 Bucket Name

demo-us-bkt

VPC CIDR

20.0.0.0/16

Number Of Availability Zones

2

ListOfAzs (List of Availability Zones)

us-west-1a,us-west-1b

Name of the Management Subnets

MgmtSubnet-1,MgmtSubnet-2

MgmtSubnetCidrs

20.1.250.0/24,20.1.251.0/24

Name of the Inside Subnets

InsideSubnet-1,InsideSubnet-2

InsideSubnetCidrs

20.1.100.0/24,20.1.101.0/24

Name of the Outside Subnets

OutsideSubnet-1,OutsideSubnet-2

OutsideSubnetCidrs

20.1.200.0/24,20.1.201.0/24

Name of the Lambda Subnets

LambdaSubnet-1,LambdaSubnet-2

Lambda Subnet CIDR

20.1.50.0/24,20.1.51.0/24

Step 6

Click Next.

Step 7

Click Next on the Configure Stack Options window.

Step 8

On the Review page, review and confirm the settings.

Step 9

Click Create Stack to deploy the infrastructure_gwlb.yaml template and create the stack.

Step 10

After the deployment is complete, go to Outputs and note the S3 Bucket Name.

Management Center - Configure Network Infrastructure in Management Center for Threat Defense Virtual

Create and configure objects, device droups, health check port, and access policies, in the Management Center for the registered Threat Defense Virtual.

Create a Host object

Procedure

Step 1

Log in to the Management Center.

Step 2

Choose Objects > Object Management.

Step 3

Choose Network from the list of object types.

Step 4

Choose Add Object from the Add Network drop-down menu.

Step 5

Enter a Name - aws-metadata-server.

Step 6

Enter a Description.

Step 7

In the Network field, select the Host option and enter the IPv4 address - 169.254.169.254.

Step 8

Click Save.

Create a Port object

Procedure

Step 1

Log in to the Management Center.

Step 2

Choose Objects > Object Management.

Step 3

Choose Port from the list of object types.

Step 4

Choose Add Object from the Add Port drop-down menu.

Step 5

Enter a Name - test-port-object.

Step 6

Choose a Protocol. You must choose the protocol that you have entered for the Host object type. Depending on the protocol you chose, constrain by Port.

Step 7

Enter 8080. Note that you can customise the port number that you enter here as per your requirement.

Note

 

You must constrain the object by port if you chose to match All protocols, using the Other drop-down list.

Step 8

Click Save.

Create Security Zone and Interface Group Objects

Procedure

Step 1

Choose Objects > Object Management.

Step 2

Choose Interface from the list of object types.

Step 3

Click Add > Security Zone or Add > Interface Group.

Step 4

Enter a Name - Inside-sz/Outside-sz.

Step 5

Choose an Interface Type.

Step 6

From the Device > Interfaces > drop-down list, choose a device that contains interfaces you want to add.

Step 7

When you create or edit a security zone, the Device > Interfaces > drop-down list displays the cluster names for high-availability devices. Choose the cluster that contains the interfaces you want to add.

Step 8

Choose one or more interfaces.

Step 9

Click Add to add the interfaces you chose, grouped by the device.

Step 10

Click Save.

Add Device Group

The Management Center allows you to group devices so you can easily deploy policies and install updates on multiple devices. You can expand and collapse the list of devices in the group.

Procedure

Step 1

Choose Devices > Device Management.

Step 2

From the Add drop-down menu, choose Add Group.

Step 3

To edit an existing group, click Edit (edit icon) for the group you want to edit.

Step 4

Enter a Name - aws-ngfw-autoscale-dg.

Step 5

Under Available Devices, choose one or more devices to add to the device group. Use Ctrl or Shift while clicking to choose multiple devices.

Step 6

Click Add to include the devices you chose in the device group.

Step 7

Click OK to add the device group.

Enable Port 443 (HTTP) for Health Check Probe

If you are using port 443 (HTTP) for the health check probe, perform the following procedure to enable the port for the health check probe.

Procedure

Step 1

Choose Devices > Platform Settings > HTTP Access.

Step 2

Select the Enable HTTP Server checkbox.

Step 3

Enter 443 in the Port field.

Step 4

Click + Add.

Step 5

Select the relevant IP Address from the drop-down list.

Step 6

From the Available Zones/Interfaces window, select the outside interface that is connected to the GWLB or the outside subnet.

Step 7

Click Add to add that interface to the Selected Zones/Interfaces window.

Step 8

Click OK.

Step 9

Click Save.

Create a Basic Access Control Policy

When you create a new access control policy, it contains default actions and settings. After creating the policy, you are immediately placed in an edit session so that you can adjust the policy to suit your requirements.

Procedure

Step 1

Choose Policies > Access Control.

Step 2

Click New Policy.

Step 3

Enter a unique Name - aws-access-policy and Description.

Step 4

Specify the initial Default Action - Block all traffic.

Step 5

Click Save.

Step 6

Click the Edit icon for the new policy that you created.

Step 7

Click Add Rule.

Step 8

Set the following parameters:

  • Name: inside-to-outside

  • Insert: into Mandatory

  • Action: Allow

  • Add a source zone and destination zone.

Step 9

Click Apply.

Local Host - Update the Configuration JSON File

The configuration.json file is in the lambda_python_files folder that you downloaded from GitHub. Update the parameters in the configuration.json file with the parameters set up by you in the management center.

The scripts in the configuration.json file are as given below.

"licenseCaps": ["BASE", "MALWARE", "THREAT"],   // Management center virtual licenses 
  "fmcIpforDeviceReg": "DONTRESOLVE",   // Management center virtual IP address 
  "RegistrationId": "cisco",  // Registration ID used while configuring the manager in the Threat defense virtual
  "NatId": "cisco",  // NAT ID used while configuring the manager in the Threat defense virtual
  "fmcAccessPolicyName": "aws-access-policy",  // Access policy name configured in the Management center virtual
  "fmcInsideNicName": "inside", //Threat defense virtual inside interface name
  "fmcOutsideNicName": "outside", //Threat defense virtual outside interface name
  "fmcInsideNic": "GigabitEthernet0/0", // Threat defense virtual inside interface NIC Name - GigabitEthernet for c4 instance types, and TenGigabitEthernet for c5 instance types)
  "fmcOutsideNic": "GigabitEthernet0/1", // Threat defense virtual outside interface NIC Name - GigabitEthernet for c4 instance types, and TenGigabitEthernet for c5 instance types
  "fmcOutsideZone": "Outside-sz", //Outside Interface security zone name that is set in the Management center virtual
  "fmcInsideZone": "Inside-sz", //Inside Interface security zone name that is set in the Management center virtual
  "interfaceConfig": [
    {
      "managementOnly": "false",
      "MTU": "1500",
      "securityZone": {
        "name": "Inside-sz"
      },
      "mode": "NONE",
      "ifname": "inside",
      "name": "GigabitEthernet0/0"
    },
    {
      "managementOnly": "false",
      "MTU": "1500",
      "securityZone": {
        "name": "Outside-sz"
      },
      "mode": "NONE",
      "ifname": "outside",
      "name": "GigabitEthernet0/1"
    }
  ],  // Interface-related configuration
  "trafficRoutes": [
    {
      "interface": "inside",
      "network": "any-ipv4",
      "gateway": "",
      "metric": "1"
    }
  ] // This traffic route is used for the Threat defense virtual instance's health check
}

Local Host - Configure Infrastructure Components using AWS CLI on the Local Host

The templates do not create the Lambda layer and encrypted passwords for the threat defense virtual and management center. Configure these components using the procedures given below. See AWS Command Line Interface for more information on the AWS CLI.

Procedure

Step 1

Create Lambda Layer Zip File.

Create a python folder on your Linux host and then create the Lambda layer.

  1. Create a python folder in your Linux host, such as Ubuntu 22.04.

  2. Install Python 3.9 on your Linux host. A sample script to install Python 3.9 is given below.

    $ sudo apt update
$ sudo apt install software-properties-common
$ sudo add-apt-repository ppa:deadsnakes/ppa
$ sudo apt install python3.9
$ sudo apt install python3-virtualenv
$ sudo apt install zip
$ sudo apt-get install python3.9-distutils
$ sudo apt-get install python3.9-dev
$ sudo apt-get install libffi-dev

  3. Create a lambda layer zip file, autoscale_layer.zip, in your Linux environment. This file provides essential Python libraries for Lambda functions.

    Run the following scripts to create the autoscale_layer.zip file. 

    #!/bin/bash
mkdir -p layer
mkdir -p python
virtualenv -p /usr/bin/python3.9 ./layer/
source ./layer/bin/activate
pip3 install attrs==23.1.0
pip3 install bcrypt==3.2.2
pip3 install certifi==2022.12.7
pip3 install cffi==1.15.1
pip3 install chardet==3.0.4
pip3 install cryptography==2.9.1
pip3 install idna==2.10
pip3 install jsonschema==3.2.0
pip3 install paramiko==2.7.1
pip3 install pycparser==2.21
pip3 install pycryptodome==3.15.0
pip3 install PyNaCl==1.5.0
pip3 install pyrsistent==0.19.3
pip3 install requests==2.23.0
pip3 install scp==0.13.2
pip3 install six==1.16.0
pip3 install urllib3==1.25.11
echo "Copy from ./layer directory to ./python\n"
cp -r ./layer/lib/python3.9/site-packages/* ./python/
zip -r autoscale_layer.zip ./python

  4. After creating the autoscale_layer.zip file, copy the autoscale_layer.zip file to the lambda-python-files folder that is downloaded from GitHub.

Step 2

(Optional) Create Encrypted Passwords for the Threat Defense Virtual and Management Center.

If a KMS ARN value has been entered in the infrastructure_gwlb.yaml template file, the passwords that you set up in the threat defense virtual and management centre have to be encrypted. See Finding the key ID and key ARN to identify the key ARN using the AWS KMS console. On your local host, encrypt the password by running the following AWS CLI command.
$ aws kms encrypt --key-id <KMS-ARN> --plaintext 'MyC0mplIc@tedProtect1oN'
{
    "KeyId": "KMS-ARN", 
    "CiphertextBlob": 
"AQICAHgcQFAGtz/hvaxMtJvY/x/rfHnKI3clFPpSXUU7HQRnCAFwfXhXHJAHL8tcVmDqurALAAAAajBoBgkqhki
G9w0BBwagWzBZAgEAMFQGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQM45AIkTqjSekX2mniAgEQgCcOav6Hhol
+wxpWKtXY4y1Z1d0z1P4fx0jTdosfCbPnUExmNJ4zdx8="
}
$
The value of CiphertextBlob is the encrypted password. Use this password as the value of the NGFWv Password (threat defense virtual password) or the FMC Password for AutoScale Automation (management center password) parameter in theinfrastructure_gwlb.yaml file. You can also use this password as the value of the FMC Password for Publishing Metrics to CloudWatch.

Local Host – Create Target Folder

Use the command given below to create a target folder containing the files that have to be uploaded to the Amazon S3 bucket.

python3 make.py build

This creates a folder named ‘target’ on your local host. The target folder contains the zip files and yaml files required for the deployment of the auto scale solution.

Local Host - Upload AWS GWLB Auto Scale Solution Deployment Files to the Amazon S3 Bucket

Use the command given below to upload all the files in the target directory to the Amazon S3 bucket.

$ cd ./target

$ aws s3 cp . s3://demo-us-bkt --recursive

Amazon CloudFormation console - Deploy the Auto Scale Solution for the Threat Defense Virtual using GWLB

Procedure

Step 1

On the AWS Management console, go to Services > Management and Governance > CloudFormation > Stacks, and click the stack that was created by the template.

Step 2

Click Create stack > With new resources(standard).

Step 3

Select Upload a template file, click Choose File, and select deploy_ngfw_autoscale_with_gwlb.yaml from the target folder.

Step 4

Click Next.

Step 5

On the Specify stack details page, enter a name for the stack.

Step 6

Provide values for the input parameters in the deploy_ngfw_autoscale_with_gwlb.yaml template.

Stack Name: Threat-Defense-Virtual

Parameter

Values

Pod Configuration

  

Autoscale Group Name Prefix

NGFWv-AutoScale

Pod Number

1

Autoscale Email Notification

username@cisco.com

Infrastructure Details

  

VPC ID

vpc-05277f76370396df4

S3 Bucket Name

demo-us-bkt

Subnets for Lambda Functions

subnet-0f6bbd4de47d50c6b,subnet-0672f4c24156ac443

Security Groups for Lambda Functions

sg-023dfadb1e7d4b87e

Number of Availability Zones

2

Availability Zones

us-west-1a, us-west-1b

Subnets List for NGFWv Management Interface

subnet-0e0bc4961de87b170

Subnets List for NGFWv Inside Interface

subnet-0f6acf3b548d9e95b

Subnets List for NGFWv Outside Interface

subnet-0cc7ac70df7144b7e

GWLB Configuration

  

Enter a port for NGFWv instance health check

22

Cisco NGFWv Instance Configuration

  

NGFWv Instance type

C4.xlarge

NGFWv Instance License type

BYOL

Assign Public IP for NGFWv from AWS IP Pool

true

Security Groups for NGFWv Instance

sg-088ae4bc1093f5833

Security Group for NGFWv Instance inside

sg-0e0ce5dedcd9cd4f3

Security Group for NGFWv Instance outside

sg-07dc50ff47d0c8126

NGFWv AMI-ID

ami-00faf58c7ee8d11e1

KMS Master Key ARN (conditional)

NGFWv Password

W1nch3sterBr0s

FMC Automation Configuration

  

FMC host IP address

3.38.137.49

FMC Username for AutoScale Automation

autoscaleuser

FMC Password for AutoScale Automation

W1nch3sterBr0s

FMC Device Group Name

aws-ngfw-autoscale-dg

Performance Tier value for FMCv licensing

FTDv20

FMC Device Group Metrics Publish Configuration

  

Publish Custom Metrics from FMC

TRUE

FMC Username for Publishing Metrics to CloudWatch

metricuser

FMC Password for Publishing Metrics to CloudWatch

W1nch3sterBr0s

Scaling Configuration

  

Lower,Upper CPU Thresholds

10,70

Lower,Upper Memory Thresholds

40,70

Step 7

Click Next on the Configure Stack Options window.

Step 8

On the Review page, review and confirm the settings.

Step 9

Click Create Stack to deploy the deploy_ngfw_autoscale_with_gwlb.yaml template and create the stack.

This completes deployment of both the templates that are required to set up the auto scale solution for threat defense virtual using GWLB.

Amazon EC2 console - Edit the Number of Instances in the Auto Scale Group

By default, the Auto Scale group has the minimum and maximum number of threat defense virtual instances set to 0 and 2 respectively. Change these values as per your requirement.

Procedure

Step 1

On the AWS Management console, go to Services > Compute > EC2, and click Auto Scaling Groups.

Step 2

Select the auto scaling group created by you and click Edit to modify the values in the Desired capacity, Minimum capacity, Maximum capacity fields as per your requirement. These values correspond to the number of threat defense virtual instances that you want to bring up for the auto scaling functionality. Set the Desired capacity to a value that is within the minimum and maximum capacity values.

Step 3

Click Update.


Note

We recommend that you launch only one threat defense virtual instance and verify that the behaviour of this instance is as expected. You can then launch more instances as per your requirement.

Amazon VPC dashboard console - Create the GWLB Endpoint and Configure Routing for the Customer VPC

You have to create the GWLB endpoint and configure routing for the customer VPC after deploying both the CloudFormation templates.

Create the GWLB Endpoint

Procedure

Step 1

On the AWS Management console, go to Services > Networking & Content Delivery > VPC > Endpoint Services.

Step 2

Click Create Endpoint Service

Step 3

Under Load balancer type, choose Gateway.

Step 4

Under Available load balancers, choose the Gateway Load balancer that was created as part of the Auto scale deployment.

Step 5

Click Create.

Step 6

Copy the Service name of the newly created endpoint service.

Step 7

Go to Services > Networking & Content Delivery > VPC > Endpoints.

Step 8

Click Create endpoint.

Step 9

Under Service category, choose Other endpoint services.

Step 10

For Service name, enter the name of the service, and then choose Verify service.

Step 11

In the VPC field, select the VPC, App VPC, in which to create the endpoint.

Step 12

Under Subnets, select the subnet, Egress subnet, in which to create the endpoint.

Step 13

For IP address type, choose the IPv4 option to assign IPv4 addresses to the endpoint network interfaces.

Step 14

Click Create endpoint.

Step 15

Go to Services > Networking & Content Delivery > VPC > Endpoint services, click the Endpoint Connections tab, choose the Endpoint ID that you created earlier, and click Actions > Accept endpoint connection request.

Configure Routing for the Customer VPC

Procedure

Step 1

On the AWS Management console, go to Services > Networking & Content > Virtual Private Cloud > Route tables.

Step 2

Create the Ingress Route Table and perform the following steps:

  1. Click Actions > Edit routes.

  2. For IPv4, click Add route. For Destination, enter the IPv4 CIDR block 10.0.1.0/24 of the subnet for the application servers. For Target, select the VPC endpoint.

  3. Click Save changes.

  4. In the Edge Associations tab, click Edit edge associations, and choose Internet gateway.

  5. Click Save changes.

Step 3

Select the route table for the subnet with the application servers and perform the following steps:

  1. Click Actions > Edit routes.

  2. For IPv4, click Add route. For Destination, enter 0.0.0.0/0. For Target, select the VPC endpoint.

  3. Click Save changes.

Step 4

Select the route table for the subnet with the Gateway Load Balancer endpoint, and perform the following steps:

  1. Click Actions > Edit routes.

  2. For IPv4, click Add route. For Destination, enter 0.0.0.0/0. For Target, select the internet gateway.

  3. Click Save changes.

Amazon CloudWatch - Validate Deployment

Once the template deployment is successful, go to the Amazon CloudWatch console to ensure that logs are being collected and the required alarms have been created.

Logs

Check the log files to troubleshoot any issues with Management Center connectivity.

Procedure

Step 1

On the AWS Management console, go to Services > Management & Governance > CloudWatch.

Step 2

Click Log groups and click any log group displayed here to view the logs.

Alarms

Ensure that the required alarms have been created on the Amazon CloudWatch console.

Procedure

Step 1

On the AWS Management console, go to Services > Management & Governance > CloudWatch.

Step 2

Click Alarms > All Alarms to display the list of alarms along with the conditions which will trigger the scale-out and scale-in functions.