Learning HCX-Part 1: Introduction to HCX

VMware Hybrid Cloud Extension (previously known as HCX technologies) was announced by VMware last year during VMworld 2017 Europe and it aimed at following use cases:

  • Simplified Data Center Migration: Seamless migration of appliactions from on-premise to cloud. 
  • Infrastructure Hybridity: Hybrid Cloud Extension enables seamless cloud on-boarding.
  • Disaster Recovery: In the event of a disaster, Hybrid Cloud Extension recovers the networking layer. Traffic routes are maintained as before the disaster, resulting in high-speed disaster recovery with low downtime.
  • Multi-Cloud Application Support: Hybrid Cloud Extension enables application components to exist in the multi-cloud world. 

So what exactly is VMware Hybrid Cloud Extension?

VMware Hybrid Cloud Extension is a SaaS offering that provides application mobility and infrastructure hybridity across different vSphere versions, on-premises and in the cloud.


To know more HCX, please see the VMware HCX FAQ section.

VMware journey from HCM to HCX

Before HCX solution, VMware offered a similar product named “Hybrid Cloud Manager (HCM) ” to support their vCloud Air service. Customers were using HCM to migrate workloads from their on-premise to vCloud Air using HCM. Also it offered features like L2 network stretch, cold migration and vMotion to cloud.

Many of you might have seen the Hybrid Cloud Manager icon in Web Client and when you click on it it used to ask to connect to vCloud Air. But before you could actually use it, you had to deploy the HCM appliance and register it with your on-premise vcenter server and then you can connect it to vCloud Air service.

Last yer VMware sold their vCloud Air service to OVH and VMware focus shifted from Cloud Provider to Cloud Enabler. VMware revised their Hybrid Cloud strategy to support other VMware-based cloud such as IBM Softlayer, OVH Cloud and lately VMware Cloud on AWS.

With HCX solution, the main goal of VMware is to deliver a truly seamless infrastructure hybridity service between on-premises and the cloud. 

What makes HCX so special?

There are 2 mind blowing feature that HCX offers:

1: vMotion ToCloud: This is also known as live migration. When you initiate a live migration of VM from on-premise to cloud, VM is permanently moved to cloud when migration process completes. Now you may be thinking that for vMotion we need source and destination as Esxi host and if the source host is in on-premise and destination host is in cloud, how this is happening? The answer for this is via HCX Cloud Gateway (CGW) vitual machine. 

When CGW is deployed, you will see a dummy host appearing in your on-premise and cloud infrastructure and this dummy host is called Mobility Agent (MA). When you initiates vMotion to cloud, this MA host securely proxy vMotion traffic from the on-premises environment out to the CGW VM which then gets transfered to cloud and lands on CGW instance of cloud and from there to the destination Esxi host.

2: Bulk Migration: Bulk migration helps you to migrate many workloads together to the cloud. Bulk migration uses the native vSphere Replication technology to replicate VM’s to cloud and when initial sync is completed, you can specify a scheduled switch over time . where the deltas are pushed to VM which got replicated to cloud and VM’s are finally moved to cloud. Although you have an option to keep a copy of VM in your on-premise. 


Hybrid Cloud Extension Components

There are 2 versions of HCX i.e HCX Enterprise and HCX Cloud. HCX Enterprise is deployed in on-premise and HCX cloud is deployed usually on the cloud provider side. Once you deploy HCX Enterprise in your on-premise, you can register it to HCX Cloud using the URL provided by service provider.

A single HCX-Enterprise instance can handle multiple cloud connections and same stands true for for HCX-Cloud. Apart from HCX Enterprise and HCX Cloud, we have 3 more components that are part of the HCX deployment:

  • Cloud Gateway (CGW)
  • WAN Optimizer
  • Layer2 Concentrator

These are deployed as virtual machines within the HCX installation (same like how you deploy an edge gateway within NSX). I am not discussing about these components in this post because I want to discuss these separately when we will be actually deploying this.

I am wrapping up this introduction post here itself as I am still trying to learn more and more about this everyday. However you can learn more about HCX from below links:

HCX Hands on Lab

HCX Feature Walkthrough


HCX Installation & User Guide

HCX CLI User Guide

I hope you find this post informational. Feel free to share this on social media if it is worth sharing. Be sociable 🙂