VMware vMotion vs. Storage vMotion Comparison

Virtualization technologies are becoming increasingly popular as the technology industry continues to evolve. Virtualization enables you to optimize your infrastructure, reduce costs, and gain greater control over your IT environment.

Suppose you must relocate a virtual machine or its storage, yet the services running on it must remain undisturbed. In that case, you can create multiple virtual machines on a single ESXi host and choose the desired one. This process is known as live migration, allowing you to switch across virtual machines. At the same time, the services remain running without any interruption.

Two of the most popular virtualization technologies for live migration are VMware vMotion and Storage vMotion. They enable you to move virtual machines (VMs) and their storage between physical servers, storage devices, and other data centers with minimal downtime. Although both are similar in some ways, they have significant differences.

The key difference exists in the way both technologies perform the migration of VMs and associated storage. To know which of the two technologies to use, you need to understand how they operate. So, in this blog, we will provide an overview of VMware vMotion and Storage vMotion and discuss their critical differences. We will also provide an overview of the advantages and challenges associated with each technology.

With this information, you can make informed decisions on utilizing these technologies to maximize your virtualization investment.

Overview of VMware vMotions and How It Operates

VMware vMotion is a technology that enables the live migration of a virtual machine from one physical server to another without any downtime. This process helps maximize the performance and availability of your VMs by taking advantage of server consolidation, maintenance, and load-balancing capabilities. Apart from the advantages of reduced downtime, your team will notice further improvements in optimizing your data center, such as combining many resources and getting the most out of the hardware.

Furthermore, it will be possible to stop wide-scale interruptions or data loss by actively transferring virtual machines away from older machines. These include machines reaching the end of their lifespan or devices that consistently underperform. In other words, vMotion will improve your IT infrastructure’s scalability and availability. Plus, it increases adaptability and hardware optimization.

How Vmware vMotion Works

vMotion works by creating a virtual machine clone on the destination server, copying the source server’s RAM and CPU state information. And then quickly establishing the network connections between the source and destination servers.

When preparing a VMware ESXi host for vMotion, there are several factors you must consider. These include:

• Ensuring the CPU architecture is compatible between the source and target ESXi host.
• Having access to the data stores where the virtual machine VMDKs are stored.
• Using the same label for VMware Standard vSwitches (VSS) so that network connectivity is maintained when vMotioning a virtual machine.
• Ensuring the physical network connections and labels are consistent across the ESXi hosts.
• Having a minimum of a gigabit network connection.
• Enabling a vmkernel port with the vMotion service.

Challenges of Using VMware vMotion

While the benefits of using VMware vMotion are numerous, this fantastic tool also has drawbacks that you should understand as a business owner.

One of the main drawbacks is that vMotion requires a live connection between the source and destination servers. This glitch means if the connection is lost, the migration will fail, and the virtual machine will not be able to continue running. Additionally, the migration process might take a long time. In that case, the virtual machine may become unresponsive, causing the migration to take longer.

Another issue with vMotion is that it requires significant resources from both the source and destination servers. The migration process will only succeed if both servers have enough resources available. Furthermore, if the vMotion process is interrupted, the virtual machine may not be able to continue running.

Lastly, vMotion can be challenging to manage and troubleshoot, especially if the environment is extensive. Ensuring the domain is configured correctly and maintained is crucial to successful migrations.

Overview of Storage vMotion and How it Works

Storage vMotion is a feature built into the vSphere product (vSphere Suites). It allows the live migration of the storage associated with a virtual machine from one datastore to another while the virtual machine remains running.

While vMotion migrates a VM’s RAM and CPU state, Storage vMotion migrates the entire content of the virtual disk file. Plus, all of the VM’s data and applications from one datastore to another. This process allows for easier storage management and makes it possible to move data from one storage type to another without impacting the VM’s running. Storage vMotion offers a significant advantage when it comes to maintenance activities. It enables you to implement normally intrusive and disruptive storage services without disrupting virtual machines, like VMFS upgrades.

Through storage vMotion, VMs can be migrated from one storage device to another (while they are running), enabling the completion of maintenance. Moreover, by relocating virtual machines, storage vMotion can modify storage load or remaining capacity.

How Storage vMotion Works

vMotion operates in three main steps. The first step is to select the virtual machines you want to move. You can select multiple VMs at once or a single VM.

The second step is to select the destination data store where you want to move the VMs. Finally, the third step is to initiate the Storage vMotion process.

Beginning the Storage vMotion migration, Storage vMotion uses vSphere’s changed block tracking (CBT) technology to duplicate the data from the transferred virtual machine. CBT is necessary for this step as it helps keep the data reliable throughout moving the VM.

Next, the server will have to check the modules created by CBT again to make a copy of the VM in its new target place. This procedure continues until the original VM and the copy in the new location are in alignment. After stopping the process, the system redirection to the new site of the VM’s image then occurs. To be able to carry out the live migration process, there are specific prerequisites to be met. These include:

• The virtual disks of the virtual machine must be in a persistent mode or RDMs.
• The virtual machine cannot undergo the migration process using storage vMotion while VMware Tools is installed.
• The VMFS versions need to be taken into account when transitioning from a newer version to an older one, as the disk size may need to be adjusted.
• The host must have a valid storage vMotion license.
• In the case of VMware vSphere hosts running ESXi 4.0 and later, the vMotion configuration will not be necessary.

Challenges of Using storage vMotion

As discussed earlier, Storage vMotion is an incredible tool for managing the live migration of your VMs. However, it also probes some drawbacks you must understand before choosing this tool for your migration process.

One of the main drawbacks is that it takes a more extended period. This issue is because Storage vMotion has to transfer the entire contents of a virtual disk file, which can take a significant amount of time. Additionally, if Storage vMotion is interrupted during the process, the virtual machine may not be able to continue running.

In addition, Storage vMotion requires a significant amount of network bandwidth, which can be challenging to manage in a large environment. Also, Storage vMotion can be difficult to configure and manage, especially if the domain is large.

Finally, Storage vMotion can be expensive, as it requires additional storage hardware to migrate the contents of the virtual disk file.

How does Storware Backup and Recovery support VMware workload management?

Storware Backup and Recovery is a data protection solution that enables the creation of backups and recovery of VMs and other data in case of system failures, disasters, or data corruption. While this solution can help you restore VMs to a previous state, it cannot provide the live migration capabilities of vMotion and Storage vMotion. However you can enable the live migration option during instant restore. It will automatically start the disks migration to the chosen storage after the VM is restored and powered on.

It’s worth noting that backup and recovery solutions and live migration features like vMotion and Storage vMotion are complementary and serve different purposes. Both are important for ensuring the availability, integrity, and recoverability of virtualized workloads in the event of hardware or software failures.

Having backup copies of virtual machines and other resources processed and stored in VMware ecosystems is now a must. The ability to restore this data in a selected location or migration between hosts is one of the numerous functionalities of Storware Backup and Recovery. In addition, we get a lot of additional functionalities that allow these processes to be automated and additionally protected against cyber threats. Feel free to test it out!

Comparison of VMware vMotion and Storage vMotion

VMware vMotion and storage vMotion are handy tools for managing virtual environments, but they are different. While they have a few similarities, they ultimately serve other purposes and have some notable differences.

• Similarities between VMware vMotion and Storage vMotion

The primary similarity between VMware vMotion and Storage vMotion is that they are both used to manage virtual environment components. VMware vMotion moves virtual machines (VMs) between physical servers. In contrast, Storage vMotion moves virtual disks between storage locations. Both technologies mainly make virtualization more efficient and reduce downtime during migration processes. Another similarity between the two technologies is their ability to move VMs and their data without disruption. Both technologies allow for the seamless transfer of virtual machines and their data from one location to another, making it easier to manage your virtual environments without interruption.

• Differences between VMware vMotion and Storage vMotion

The primary difference between VMware vMotion and Storage vMotion is the type of data they move. VMware vMotion moves VMs and their associated components, including the operating system, applications, settings, and configurations. In contrast, Storage vMotion moves the virtual disk associated with the VM. Another difference between the two technologies is the time it takes to move the data. VMware vMotion is generally much faster than Storage vMotion, as Storage vMotion requires more time to move the associated data. Additionally, Storage vMotion is effective when only moving data between physical storage locations. In contrast, VMware vMotion can move VMs between physical servers.

Final Thought

VMware vMotion and Storage vMotion are powerful tools that allow for workloads’ seamless and efficient movement between different environments. VMware vMotion enables virtual machines’ live migration and associated data between different vSphere hosts. At the same time, Storage vMotion allows for the dynamic relocation of virtual disks between other datastoress.

Both technologies are essential for reducing downtime, maximizing resource utilization, and ensuring optimal performance of your virtual workloads. Therefore, before choosing between the two, consider the IT infrastructure in place, finances, and your organization’s needs.