What is CloudVision and what does it do for my data center?
Today let’s talk about Software Defined Data Centers and how we can make our lives a little easier by automation, specifically how we can tie our underlay and overlay together.
Our software-defined data centers today are typically comprised of two main areas. Our “underlay”, which is typically deployed in a spine and leaf layout, then our “overlay”, which in this case will be VMware’s NSX platform. In a lot of cases, people try to treat these as two separate entities, which we believe is a pitfall. By having the ability to tightly integrate the underlay and overlay together, it allows us to have end-to-end control and visibility into our datacenter environment, as well as many other benefits.
CloudVision can be thought of as an underlay automation component and is delivered by Arista. CloudVision allows for a single control point for our entire underlay environment. This provides end-to-end control, automated provisioning, centralized management, real-time event correlation and real-time visibility of our underlay network, as well as providing a simple integration into our overlay environment.
CloudVision is made up of two primary “components”: CloudVision portal (CVP) and CloudVision Exchange (CVX). CVP provides a GUI based method to control our physical Arista switches. CVX, at least in this topic, will handle the back end VXLAN provisioning.
Integration of CloudVision into NSX
One of the goals of integrating CloudVision into NSX is to provide management of hardware gateways, otherwise known as a hardware VTEP (VXLAN Tunnel End-Point). This hardware gateway becomes an NSX gateway for VXLAN traffic moving between the virtual and physical workloads. One of the typical use-cases is using a pair of hardware VTEPs (ToR Switches) to provide an active-active top-of-rack deployment. From the NSX side, it sees the two hardware VTEPs as one logical unit, thus providing redundancy and performance benefits.
Below in Figure 1, you can see an example layout for the software layer 2 gateway that NSX provides.
In Figure 2, you see the integration of third-party components to achieve layer-2 gateway functionality in hardware. This provides the VXLAN to VLAN communications, as well as providing a high port density and low latency method to connect the physical to the virtual world.
Another key function that occurs between NSX and CloudVision is the communication between the NSX controller and hardware gateway. The two use the OVSDB protocol (TCP port 6640) to exchange information. The NSX Controller is the client, and the HSC (Hardware Switch Controller) is the server side. In the case with NSX and CloudVision, CloudVision is the HSC and acts as a single point of integration to NSX for all of the Arista gateways.
VXLAN Control Service
Since we will be using VXLAN, we will need something to synchronize this information across our infrastructure. CloudVision uses the VCS, or VXLAN Control Service to aggregate network-wide VXLAN state for integration and orchestration with NSX. CloudVision Exchange (CVX) handles this part. The basics of getting this setup and running in your environment would be as follows.
- Enable VXLAN Control Services (VSC) on the ToR switches and on CloudVision CVX
- Enable HSC services on CloudVision CVX.
- Configure NSX
Let’s take a look at the commands needed on CVX and the ToR switches to accomplish the task above.
The first thing we would do is to tell the ToR switches that CloudVision will manage the VXLAN Control Service.
ToR(config-mgmt–cvx)#server host 10.10.10.1 [Symbol] This is telling the switch what the management IP off CloudVision uses to listen for client connections.
Next, we will need to tell the ToR switches that they are a client and that they should sync their VXLAN tables with CloudVision. To do this we use the vxlan–contoller-client command under interface vxlan 1 as shown below.
ToR(config)#Interface vxlan 1
We will then need to configure CloudVision CVX to be the VXLAN controller. To do this we use the following commands.
At this point, we have configured CloudVision Exchange to speak and interact with the ToR switches. Now we will need to enable HSC on CloudVision CVX. We use the following commands to accomplish this.
Lastly, we will need to tell CloudVision Exchange where the NSX controller lives at. This is needed to establish the OVSDB communication between CloudVision and the NSX controller.
cvx(config-cvx–nsx)#manager 10.114.221.234 [Symbol] IP address of the NSX Controller.
Note with some installations you may need to change the default port to the port the OVSDB protocol uses (6640) as shown below.
cvx(config-cvx–nsx)#manager 10.114.221.234 6640
Note: There are typically redundant NSX Controllers. Only one of them needs to be entered. The others will be automatically discovered.
At this point, we have done everything we need to do on the ToR and CloudVision side, with one exception. We want to grab the HSC certificate from CloudVision CVX. Below we see the command we need to enter to view the certificate, so we can copy and paste it into NSX.
cvx#show hsc certificate [Symbol] copy the output for the certificate so we can paste it into NSX in the next few steps.
Now let’s move over the NSX side and get this guy set up.
Once we are inside the Networking and Security area, click on Service Definitions, then Hardware Device. Click on the green plus sign to add a new hardware device. Next, give the new hardware device a name, description and lastly paste the certificate you copied over from the output of the show hsc certificate command earlier. You should see something similar to what is below in Figure 3.
Note: BFD is enabled by default. VMware will only support configurations running BFD
Now we will select the nodes that we would like to participate in the replication cluster. This is enabled from the same screen above (Service Definitions->Hardware Devices). Select the host you want in the replication cluster from the left pane, then click the arrow facing to the right to add them as shown in Figure 4 below.
At this point, NSX and CloudVision have been mapped together and we can map a LS (Logical Switch) to any physical port/VLAN advertised by this gateway as shown below in Figure 5 and Figure 6.