 the switch dynamically creates an outbound rule to allow the traffic to return to the requestor. 21. On Tenant A - VM 11 repeat step 14. You will see that the TCPTestSucceeded has changed to True. This is because the stateful ACL is now in place. Chapter 7 How it works. Extended ACLs are applied as traffic ingresses and egresses the VM into and out of the Hyper-V switch. As the ACLs are VM-specific, they are stored in the VM's configuration file. This ensures that the ACLs are moved with the VM ensuring continuity of the ACL. For the complete range of options, it is advisable to review the TechNet article at tp://technet. microsoft.com/en-us/library/dn464289.aspr Applying rules to a list of VMs Hyper-V supports a variety of operating systems, including those that do not have inbuilt firewalls like Windows Server 2012 R2. Using the Hyper-V Extended ACLs, you can provide basic levels of protection to these guest virtual machines. Additionally, it may be a case that some users do not necessarily lock down their servers as much as the company requires. This can be typical of a short-lived server such as a test server. Through the use of PowerShell, it is possible to apply a large number of Port ACLs to virtual machines quickly and efficiently. This recipe will show you how to use a CSV file and PowerShell to apply a set of Port ACLs to multiple virtual machines. Getting ready This recipe uses a CSV file and it is recommended to create this in Microsoft Office Excel; having access to a computer with it installed would be beneficial. How to do it... The following diagram shows the high-level steps involved in this recipe: Overview of Recipe: Actions: Use PowerShell to apply a numerous Port ACLs listed in a CSV to multiple VMs Network Access Control Lists Now perform the following steps: 1. In Excel, create a new workbook. 2. Enter the following in row 1, one value per column: Action Direction Weight LocalPort Protocol 3. The following table shows the content of the CSV file that will be used in this recipe: Action Dir