One of the quickest and easiest returns on investment in the VMware product stack is VMware NSX Identity Firewall. What other product, with an hour of configuration and initial policy creation, returns such business outcomes? I’d hesitate to say there’s any such solution out there that can provide such an immediate return on investment. VMware NSX IDFW provides an incredibly valuable and easy to use solution for VDI and data center “jumpboxes” alike. With that said, I’m going to demonstrate how you can deploy and configure VMware NSX Identity Firewall in under an hour and have an identity-based security solution that can be easily inserted into any existing vSphere environment. …with or without deploying VMware NSX networking.
There are two methods IDFW uses for logon detection: Guest Introspection and/or the Active Directory Event Log Scraper. Guest Introspection is deployed on ESXi clusters where IDFW virtual machines are running. When network events are generated by a user, a guest agent installed on the VM forwards the information through the Guest Introspection framework to the NSX Manager. The second option is the Active Directory event log scraper. Configure the Active Directory event log scraper in the NSX Manager to point at an instance of your Active Directory domain controller. NSX Manager will then pull events from the AD security event log. You can use both in your environment, or one or the other. Note that if both the AD event log scraper and Guest Introspection are used, the two are mutually exclusive: if one of these stops working, the other does not begin to work as a back up.
Before we get started, let’s talk reality. While security postures such as Micro-segmentation and Zero-Trust may indeed be your desired end-state, they’re a much longer journey than Macro-segmentation or Application Fencing. With that said, you can imagine how quickly you could create Application Fencing security policies for application servers or groups in your environment and start by simply controlling user access to them. Now, with the understanding that you can accelerate your NSX Identity Firewall implementation by leveraging macro-segmentation strategies in the initial phase, you’ll quickly realize that it will allow you to create more granular micro-segmentation policies in a secondary phase.
My lab scenario will demonstrate how NSX-v Identity Firewall can quickly secure an HR, Finance and CRM application, based on the users Active Directory group. The data center consists of three clusters, one for management and two for compute resources. RegionA01-COMP02 serves the hr-web-01a, fin-web-01a and web-04a VMs that serve each HR, Finance and CRM application respectively. The web VMs are running on a stereotypical “server VLAN”, on one subnet, as commonly seen in many enterprise environments. The jumpbox or VDI desktop, win-12-jump VM, is on a “user VLAN”, in another subnet.
NSX Identity Firewall configuration requires that NSX Manager be deployed and registered with vCenter. The NSX Manager appliance is deployed from OVA via vCenter and takes about 30 minutes to complete deployment and registration to vCenter. For details on installing NSX Manager, read Install the NSX Manager Virtual Appliance.
Requirements for VMware NSX Identity Firewall are:
- NSX Manager 6.2 or greater (the latest release is recommended)
- VMware Virtual Distributed Switch or NSX N-VDS
- FQDN for NSX Manager
- NTP configured in NSX Manager to the same source as vCenter, vSphere hosts and Active Directory domain controllers
- AD account to query the domain (this user must be able to access the entire directory tree structure)
- AD read-only account with permissions to read Windows Event Log locally or via Group Policy (see MS KB)
**In NSX-v, controllers and networking components are not required
After NSX Manager has been deployed and registered to vCenter, we begin configuring IDFW Event Log Scraping by setting the LDAP and CIFs properties for directory queries and event log reading. After setting the LDAP and CIFS properties, we validate that the directory has performed a sync and that the AD event servers have populated in the Event Server fields. Guest Introspection is also deployed, to explain that configuration.
This demonstration video that I created, will guide you step-by-step through the process of configuring VMware NSX Manager to enable Identity Firewall:
Some simple best-practices for leveraging Microsoft Active Directory user groups are:
- Create new user-groups in a top level OU when possible and then nest existing groups which may be deeper in the forest.
- Limit the nesting of Active Directory user groups to three(3) deep for best performance.
- When leveraging a large enterprise forest, configure the LDAP and CIFs properties for directory queries to a smaller child domain that the user groups are in, instead of the top level forest domain.
Once you’ve finished with the installation and configuration of VMware NSX-v Identity Firewall, it’s time to map Active Directory user groups to NSX security groups and create security objects for enforcement. There are static and dynamic objects that can be leveraged. Dynamic objects yield a more simplified security policy, reducing the number of overall rules and security objects needed. Thus, dynamic object types should be used whenever possible. Static NSX object types are IP Sets, vNICs and Virtual Machine names, where as dynamic security object types contain a set of resources grouped by another construct, such as a vCenter Cluster or Datacenter, Distributed Port Group, Legacy Port Group, Logical Switch, Resource Pool or vApp.
The Object Types for an NSX-v firewall rule are: Security Group, IP Sets, Cluster, Datacenter, Distributed Port Group, Legacy Port Group, Logical Switch, Resource Pool, Virtual Machine, vApp and vNIC. With such a wide array of selection criteria, there are many object types that can be leveraged to create a strategic advantage in your security policy.
Now that we’ve configured NSX Identity Firewall, mapped Active Directory user groups to NSX security groups, we’ll create some Active Directory based rules to test access to our applications.
If you want to test blocking without changing the default Layer 3 rule, simply create a rule blocking what you need in a user defined firewall rule section above the rule you want to test. We’ll use this in in the live demo with a firewall rule called VDI to APP that blocks the VDI desktop network, leveraging an IP SET from the Internal Services security group that contains our protected web app servers. See the image below.
Now, let’s login as both users and test the access of the NetAdmin and HRAdmin users to see if they have the appropriate access.
Hope you enjoyed this post and feel free to hit me up on Twitter, LinkedIn and subscribe to my YouTube Channel with any requests for content that you’d like to see. Until next time, as the sun sets slowly in the west, I bid you a fond farewell. Adios amigos!