I think now goal of every enterprise organization is to be able to accelerate their time to business value for their customers by taking advantage of cloud and most of the enterprise customer data center are built on VMware platform and while considering cloud adoption , organizations are facing challenges listed as below:

Incompatible environments – Currently customers have various VMware vSphere versions deployed in on-premises and if these customers would like to move to the latest build of SDDC based cloud but facing trouble due to differences in versions, networking architectures, server CPUs etc.
Network complexity to the cloud – Internet/WAN technologies are complex, non-automated, and inconsistent. Setting up and maintaining VPNs, firewalls, direct connects and routing across network/co-location provider networks, and enterprise networks is not easy.
Complex application dependencies – Enterprise applications are complex and these applications interact with various other servers in the datacenter such as storage , databases, other solutions, DMZ, serious security solutions and platform applications. Application dependencies are hard to assess, customers face lots of issues in addressing these issues.

HCX enables enterprise to the over come above challenges. Delivered as a VMware Cloud Service, and available through IBM Cloud, the service enables secure, seamless interoperability and hybridity between any VMware vSphere based clouds, enabling large-scale migration to modern clouds/datacenters, and application mobility, with no application downtime. Built-in DR & security enables unified compliance, governance and control. Automated deployment makes it straightforward for service providers and enterprises to rapidly get to the desired state and shorten time to value.

HCX on IBM Cloud

HCX on IBM Cloud unlocks the IBM Cloud for on-premises vSphere environments, where you can build an abstraction layer between your on-premises data centers and the IBM Cloud. Once done, networks can be stretched securely across the HCX hybrid interconnect, which enables seamless mobility of virtual machines. HCX enables hybrid capabilities in vCenter so that workloads can be protected and migrated to and from the IBM Cloud.

HCX uses vSphere Replication to provide robust replication capabilities at the hypervisor layer , which is coupled with HCX’s ability to stretch layer 2 network, no intrusion change at the OS or application layers is required. This allows VMs to be easily migrated to and from the IBM Cloud without any change. HCX also optimizes migration traffic with inbuilt WAN optimization.

The HCX solution requires at least one VCF V2.1 or vCenter Server instance running vSphere 6.5 with the HCX on IBM Cloud service installed. This solution also requires the HCX software to be installed on-premises for the vSphere environment, in which case the HCX on IBM Cloud instance must be ordered for licensing and activation of the on-premises HCX installation.

HCX Components

HCX comprised of a Cloud side and a client side install at a minimum. An instance of HCX must be deployed per vCenter, regardless of if the vCenters where HCX is to be deployed are linked in the same SSO domain on the client or cloud side. Site configurations supported by HCX Client to Cloud are; one to one, one to many, many to one and many to many. HCX has the concept of cloud side install and customer side install.

Cloud side = destination (VCF or vCenter as a Service on IBM Cloud). The cloud side install of HCX is the “slave” instance of an HCX client to cloud relationship. It is controlled by the customer-side install.

Customer side = Any vSphere instances(Source). The client side of the HCX install is the master which controls the cloud side slave instance via it’s vCenter web client UI.

HCX Manager

The Cloud side HCX Manager is the first part of an HCX install process , which need to be deployed on the cloud side by the IBM VMware Solutions automatically. Initially it is a single deployed OVA image file specific to the cloud side in conjunction with an NSX edge load balancer-firewall which is configured specifically for the HCX role. The HCX Manager is configured to listen for incoming client-side registration, management and control traffic via the configured NSX edge load balancer / firewall.

The Client side HCX Manager a client-side specific OVA image file which provides the UI functionality for managing and operating HCX. The client side HCX manager is responsible for registration with the cloud side HCX manager and creating a management plane between the client and cloud side. it is also responsible for deploying fleet components on the client side and instructing the cloud side to do the same.

HCX Interconnect Service

The interconnect service provides resilient access over the internet and private lines to the target site while providing strong encryption, traffic engineering and extending the data center. This service simplifies secure pairing of site and management of HCX components.

WAN Optimization – Improves performance characteristics of the private lines or internet paths by leveraging WAN optimization techniques like data de-duplication and line conditioning. This makes performance closer to a LAN environment.

Network Extension Service

High throughput Network Extension service with integrated Proximity Routing which unlocks seamless mobility and simple disaster recovery plans across sites.

HCX other components are responsible for creating the data and control planes between client and cloud side. Deployed as VMs in mirrored pairs, the component consists of the following:

Cloud Gateway: The Cloud Gateway is an optional component which is responsible for creating encrypted tunnels for vMotion and replication traffic.

Layer 2 Concentrator: The Layer 2 Concentrator is an optional component responsible for creating encrypted tunnels for the data and control plane corresponding to stretched layer 2 traffic. Each L2C pair can handle up to 4096 stretched networks. Additional L2C pairs can be deployed as needed.

WAN Optimizer: HCX includes an optionally deployed Silver Peak WAN optimization appliance. It is deployed as a VM appliance. When deployed the CGW tunnel traffic will be redirected to traverse the WAN Opt pair.

Proxy ESX host: Whenever the CGW is configured to connect to the cloud side HCX site, a proxy ESXi host will appear in vCenter outside of any cluster. This ESXi host has the same management and vMotion IP address as the corresponding CGW appliance.

HCX Licenses:

Traffic on 80 and 443 must be allowed to https://connect.hcx.vmware.com
A one-time use registration key will be provided for the client-side install provided via the IBM Cloud VMware Solutions portal. A key is required for each client side HCX installation.
The Cloud side HCX registration is automatically completed by the IBM Cloud HCX deployment automation.