NSX per-VM licensing compliance

I had a customer with a production cluster of around 100 VMs. They needed to segment off a few VMs due to PCI compliance, and were looking at a large expense to create a physically separate PCI DMZ. I suggested instead the purchase of our per-VM NSX solution. We sell it in packs of 25 and it comes in at a list price of around $10K. This looked great compared to the $75K solution they were considering.

The problem with per-VM licensing is with compliance. VMware doesn’t have a KB explaining a way to make sure you aren’t using more than the number of licenses that you bought. If you add a 25-pack of NSX licenses to a cluster with 100 VMs in it, the vCenter licensing portal will show that you’re using 100 licenses but only purchased 25. VMware KB 2078615 does say “There is no hard enforcement on the number of Virtual Machines licensed and the product will be under compliance.” However, this post is related to the way per-socket licensing displays when you add it to vCenter, not related to per-VM pricing.

I’ve had a few conversations with the NSX Business Unit (NSBU) and the intent of per-VM licensing is to allow customers to use the NSX distributed firewall without physically segmenting clusters. You can run NSX-protected VMs in a cluster alongside non-NSX-protected VMs. However, you have to take some steps to ensure that you’re remaining in licensing compliance. This post shows you how to do it.

One way to do this is to avoid using ‘any’ in your firewall rules. If all of your firewall rules are VM to VM or security group to security group, all you have to do is keep the total VM count below your purchased VM count. It is difficult to craft a firewall policy without using ‘any’, though this is the simplest method if your requirements lend themselves to this method.

An alternative way is to use security tags. It’s a bit more involved but lets you have precise control over where your NSX security policy is applied.

First, I create two custom tags, Custom_NSX.FirewallDisabled and Custom_NSX.FirewallEnabled


I then assigned tags to my VMs as shown below. The disadvantage to this method is you have to keep making sure that you security tag VMs. But it does make rule writing easier. I’m only creating two groups – NSX enabled and disabled. However, there’s nothing stopping you from creating multiple tags – maybe you have a DMZ1 and DMZ2, maybe PCI and HIPAA are separate tags.

In this case, I assign all of my PCI VMs the FirewallEnabled tag and the rest of my VMs the FirewallDisabled tag.


Now, instead of going to the Firewall section, I go to Service Composer. Don’t be confused by the fact that the security groups already exist – I took the screenshot of the Security Groups tab after I created the groups.


First, I create an NSX_Disabled group with a dynamic membership of CUSTOM_NSX.FirewallDisabled.


Next, I create an NSX_Enabled security group with a dynamic membership of CUSTOM_NSX.FirewallEnabled


I then specifically exclude NSX_Disabled from the NSX_Enabled group. This guarantees that no firewall rules can touch my excluded VMs.


I create a new security policy in Service Composer


In the Firewall Rules section, NSX has something called “Policy’s Security Groups”.  If we assign the policy to the NSX_enabled security group, we can safely use an ‘any’ rule as long as the other side is ‘Policy’s Security Groups’. So source could be ‘any’ if dest is Policy’s Security Groups, or dest could be ‘any’ if source is Policy’s Security Groups. The security group we made enforces that NSX won’t apply rules on VMs that aren’t in the NSX_enabled group.


I then apply my new policy to the NSX_Enabled security group.

policy_apply security-group-select

Doing a security policy this way is a bit more involved than simply using the Firewall section of NSX, but it’s worth considering. It’s a perfect way to ensure 100% compliance in a per-VM model. It’s also helping you unlock the power of NSX – all you have to do is security tag VMs and they automatically get their security policy.


OpenStack introduction

I have a large deal on the table and they are asking about VMware’s support for OpenStack. Since I know nothing about OpenStack, other than the fact that VMware offers VMware Integrated Openstack, I decided it was time to find some training. Fortunately I have many specialists inside VMware who can help answer customer questions around VIO.

There’s plenty of VIO training internally at VMware, but I needed something even more basic, just an intro. I went to my trusty PluralSight subscription and found Eric Wright‘s Introduction to OpenStack. This is a great course to come up to speed on the basics of OpenStack in only 2.5 hours.

Unable to connect virtual NIC in vCloud Air DRaaS

I had a customer open a service request, they were in the middle of a DR test using vCloud Air DRaaS and were unable to connect 1 virtual machine to the network. It kept erroring out with a generic unable to connect error.

It turns out that their VM had a VMDK sized with a decimal point, like 50.21GB instead of just 50GB. I don’t see it often, but this sometimes happens when P2V a machine. The vCloud Director backend can’t handle the decimal point in the disk size, so it errors out.

I’m not entirely sure why the error happens, but the fix is to resize your source disk to a non-decimal number and run replication again.

A quick NSX microsegmentation example

This short post demonstrates the power of NSX. My example is a DMZ full of webservers – you don’t want any of your webservers talking to each other. If one of your webservers happens to be compromised, you don’t want the attacker to then have an internal launching pad to attack the rest of the webservers. They only need to communicate with your application or database servers.

We’ll use my lab’s Compute Cluster A as an a sample. Just pretend it’s a DMZ cluster with only webservers in it.

Compute Cluster A


I’ve inserted a rule into my Layer 3 ruleset and named it “Isolate all DMZ Servers”. In my traffic source, you can see that you’re not stuck with IP addresses or groups of IP addresses like a traditional firewall – you can use your vCenter groupings like Clusters, Datacenters, Resource Pools, or Security Tags to name a few.

Rule Source

I add Computer Cluster A as the source of my traffic. I do the same for the destination.

NSX Source Cluster


My rule is now ready to publish. As soon as I hit publish changes, all traffic from any VM in this cluster will be blocked if it’s destined for any other VM in this cluster.

Ready to publish


Note that these were only Layer3 rules – so we’re secured traffic going between subnets. However, nothing’s stopping webservers on the same subnet from talking to each other. No worries here though, we can implement the same rule at layer 2.

Once this rule gets published, even VMs that are layer 2 adjacent in this cluster will be unable to communicate with each other!

NSX layer 2 block

This is clearly not a complete firewall policy as our default rule is to allow all. We’d have to do more work to allow traffic through to our application or database servers, and we’d probably want to switch our default rule to deny all. However, because these rules are tied to Virtual Center objects and not IP addresses, security policies apply immediately upon VM creation. There is no lag time between VM creation and application of the firewalling policy – it is instantaneous!  Anybody who’s worked in a large enterprise knows it can take weeks or months before a firewall change request is pushed into production.

Of course, you still have flexibility to write IP-to-IP rules, but once you start working with Virtual Center objects and VM tags, you’ll never want to go back.

Alzheimer’s Association – Forgotten Donation

Chris Wahl just put up this blog post showing the donation of royalties from his book, Networking for VMware Administrators. I won my copy for free and at the time I promised to donate to the Alzheimer’s association. I failed to do so, but I have rectified that today.

Below is my personal donation along with VMware’s matching gift. $31.41 is the minimum donation to receive a matching gift with VMware’s matching program.  alz-donation alz-matching

Custom Views and Dashboards in vRealize Operations

This post covers a few of the most common questions my customers ask me as I demonstrate what you can do with vROps. I’m going to take you through an example of needing to frequently check the CPU ready % of your VMs – this was my customer’s most recent request, but know that you can make this happen for any metric collected by vROps.

First, we’re going to create a custom view for CPU Ready % by going to Content>Views, then clicking on the green Plus to add a new View.


I named this one “Custom-CPU Ready” and gave it a description.


Next, pick what our View looks like. In this case, I want to see all of the data in a list format, so I pick List.


Now to select the subjects – these are the objects that the View will be looking at. We want CPU Ready % on Virtual Machines, so we pick the vCenter Adapter and scroll down until we find Virtual Machine.




We now need to find the CPU Ready % metric


Double-click on it when you find it in the list on the left, it will then appear in the Data section. Change the Sort order to descending because we want to see the VM with the highest CPU ready on top.


The Availability options let you control where inside vROps the View will be usable. I lef the defaults.


You now see the custom view in the Views list.


How can we use our brand new view? We want to see the CPU ready for all VMs in the Production cluster. Go to Environment, then drill down into the vSphere World until you reach the Production cluster. Click on the Details tab, you can then scroll down and find the custom View that we created. Click on it and all of your VMs show up, sorted by highest CPU ready.



Let’s say this is a metric that you look at at daily or multiple times a day. You can create a custom dashboard so the metric is immediately visible if you’re using vROps Advanced.

To create a new dashboard, from the Home menu, click Actions, then Create Dashboard


Name the dashboard and select a layout.


We want to show a View in the widget, so we drag View over into the right pane.


Click the Edit icon in the blank View to customize it.


Click on Self Provider to allow us to specify the Production Cluster object on the left, then select our Custom CPU Ready View on the right and click Save.


The dashboard is now ready. The CPU Ready for the Production VMs will now show up in the dashboard.