What is vSphere Replication?

VMware vSphere Replication is a hypervisor-based, asynchronous replication solution for vSphere virtual machines. It is fully integrated with VMware vCenter Server and the vSphere Web Client.  vSphere Replication delivers flexible, reliable and cost-efficient replication to enable data protection and disaster recovery for all virtual machines in your environment.

vSphere Replication is an alternative to storage-based replication. It replicates virtual machines to another location or to a different cluster in the vCenter. This is an affordable solution for the small or medium enterprises without any backup solution, to restore their VMs with the latest data replicated based on RPOs set. It protects virtual machines from partial or complete site failures by replicating the virtual machines between the following sites:

  • From a source site to a target site
  • Within a single site from one cluster to another
  • From multiple source sites to a shared remote target site
  • It can be used as “Replication engine for VMware vCenter Site Recovery Manager”. (Will talk about this in detail in my future post, Step by Step procedure to integrate SRM with vSphere Replication and how it is used to protect VMs?)
  • It can also be used as “Replication engine for VMware vCloud Air Disaster Recovery”

When we deploy vSphere Replication from OVF (virtual replication (VR) appliance) installation wizard will take you through different steps and it automatically installs different system components like VR Agent, vSphere Replication Managment Server (VRMS), virtual appliance management interface (VAMI), vSphere Replication Server (VRS) and Replica Location (Target or Remote site) as shown below:

Most of the time vSphere Replication Management Server (VRMS) and vSphere Replication Server (VRS) will be the same appliance (VR appliance). Depending on the configuration, there may be need for additional VRS integrated with VRMS. VR Agent is an in-built ESXi feature gets installed during VRMS deployment, which primarily manages the replication functions and acts as a driver for vSphere replication process to work. VAMI is an interface used to configure the vSphere Appliance settings, database and vCenter/PSC SSO authentication. Replica Location can be a different cluster in same vCenter or DR site (vCenter) or Cloud provider.

How vSphere Replication Works?

Once the deployment of vSphere is completed. A primary and replica locations (target or remote site) are identified, right click on the virtual machine to be replicated and select the target location, datastore to save VM disks, set RPOs, and start replication. The selected VM can be monitored now under outgoing replications from source site and in incoming replication from target site. After replication has been configured for a virtual machine, vSphere Replication begins the initial full replication, during which the vmdk file of the VMs are replication and after the initial full synchronization, changes to the protected virtual machine are tracked and updated (changed blocks) based on the RPOs selected.

Overall vSphere Replication features and benefits

  • Simple virtual appliance deployment minimizes cost and complexity.
  • Integration with vSphere Web Client eases administration and monitoring.
  • Protect nearly any virtual machine regardless of operating system (OS) and applications.
  • Only changes are replicated, which improves efficiency and reduces network utilization.
  • Recovery point objectives (RPOs) range from 5 minutes to 24 hours and can be configured on a per–virtual machine basis..
  • Compatibility is provided with VMware vSAN, traditional SAN, NAS, and local storage.
  • Quick recovery for individual virtual machines minimizes downtime and resource requirements.
  • Optional network isolation and compression help secure replicated data and further reduce network bandwidth consumption.
  • Support for Microsoft Volume Shadow Copy Service (VSS) and Linux file system quiescing improves reliability of recovered virtual machines.

Use vSphere Replication and “Eliminate Storage Lock-In”:

If you are planning to implement Site Recovery Manager Solution, we need a replication engine to protect the virtual machines across sites. We can use Host-based replication by configuring vSphere Replication or by using storage vendor specific disk replication mechanism by configuring Storage Array Based Replication. When we implement Array based replication by using SRA, which replicates datastores to recover virtual machines workload, where we are dependent on the storage platform and the compatibility with the vSphere version etc.,

Whereas vSphere Replication is a host-based replication solution that operates at the individual virtual machine disk (VMDK) level, allowing replication of individual virtual machines between heterogeneous storage types supported by vSphere. Because vSphere Replication is independent of the underlying storage, it works with a variety of storage types including VMware vSAN, vSphere Virtual Volumes, traditional SAN, network-attached storage (NAS), and direct-attached storage (DAS). This allows you to:

  • Use differing storage technologies at linked sites, such as in SAN-to-vSAN and Fibre Channel (FC)-to-Internet Small Computer System Interface (iSCSI) arrangements
  • Repurpose older storage at the recovery site to reduce cost
  • Use secondary storage only for protected virtual machines, not the entire environment

Reduce Network Bandwidth by using vSphere Replication:

vSphere Replication copies only changed data to the recovery site to lower bandwidth utilization, improve network efficiency and enable more aggressive RPOs than a manual, full-system copy. With vSphere Replication, you can:

  • Utilize a “seed copy” of virtual machine data for the initial synchronization to reduce the amount of time required to create the initial copy
  • Ensure efficient network utilization by tracking changed disk areas and replicating only those changes
  • Optionally enable data compression to further reduce network bandwidth consumption


Hope this post is helpful, please leave your feedback below. If you have any issues during the deployment, let me know in the comments section will try to help you. Thanks..

Subscribe via Email

Enter your email address to subscribe to this site and receive notifications of my new posts by email.