Hot Add


Hot Add refers to the ability to add hardware components, such as memory or processors, to a computer system while it is running, without the need to shut down or reboot. This feature helps in reducing downtime and improving a system’s overall efficiency. Hot Add is especially beneficial in server environments where uninterrupted service is crucial.


The phonetic pronunciation of the keyword “Hot Add” is: /hɒt æd/

Key Takeaways

  1. Hot Add enables the addition of resources such as CPU and memory to virtual machines without any downtime, enhancing the runtime flexibility to meet workload demands.
  2. This feature is mainly supported by virtualization platforms such as VMware and Hyper-V, allowing efficient resource management within the virtual environment.
  3. Despite its advantages, Hot Add may require specific hardware, software, and virtual machine configurations, so it is essential to ensure compatibility and correct settings before using this feature.


The technology term “Hot Add” is important because it refers to a crucial capability of modern systems that allows components, such as memory or processing power, to be added to a running system without causing any downtime or disruption to its operations.

This feature is particularly valuable for businesses and data centers, as it ensures high availability, increased efficiency, and seamless scalability of their IT infrastructure.

By enabling system administrators to make adjustments or upgrades on-the-fly, Hot Add eliminates the need for scheduled maintenance periods, thus decreasing downtime costs and enhancing productivity.

Additionally, Hot Add promotes a more flexible and adaptable computing environment, which is essential in today’s rapidly changing technology landscape.


Hot Add is a technology feature that plays a crucial role in improving the efficiency and flexibility of modern computing systems. The primary purpose of Hot Add is to allow for the seamless addition of new resources to a system, such as memory, storage, or even processing capabilities, without the need to shut down or reboot the system.

This groundbreaking technology is especially useful in data centers, enterprise environments, and mission-critical systems where system downtime can lead to significant financial losses or disrupt essential services. By enabling Hot Add capabilities, organizations can ensure that their business operations continue running smoothly while they upgrade or expand their computing resources.

Utilizing Hot Add features not only reduces downtime but also increases the overall efficiency of IT operations, as it enables system administrators to expand resources as per the business’s evolving needs, without impacting existing applications or infrastructure. Additionally, it also helps in conserving energy and reducing maintenance costs by optimizing existing hardware deployment.

As we continue to rely on sophisticated IT systems, the adoption of Hot Add technologies will remain vital for businesses to maintain competitiveness and adapt to ever-changing technological landscapes.

Examples of Hot Add

Hot Add is a technology that allows the addition of resources such as CPU, memory, or devices to a running system without causing downtime or disruption to the system’s operations. Here are three real-world examples:

VMware vSphere (ESXi):In the world of virtualization, VMware’s vSphere is one of the most popular platforms used for deploying and managing virtual machines (VMs). The Hot Add feature in vSphere allows system administrators to dynamically allocate additional CPUs and memory to a running virtual machine without causing any disruptions or downtime. This enables businesses and organizations to maintain uptime and ensure optimum performance for applications when demand increases, without having to restart the servers or applications.

Microsoft SQL Server:Microsoft SQL Server is a widely used relational database management system (RDBMS). One of its features, called Hot Add Memory, allows the dynamic addition of physical memory to a running instance of SQL Server. This ability ensures that the database server can continue to deliver optimal performance and handle increased workloads without requiring manual intervention or causing disruptions to ongoing processes.

Hewlett Packard Enterprise (HPE) Servers – Scalable Persistent Memory:HPE’s Scalable Persistent Memory technology, available on selected HPE servers, is a hardware technology that combines the performance of traditional memory with the persistence and capacity of storage devices. This technology supports Hot Add, allowing enterprises to dynamically scale and add memory capacity to their running systems without having to shut down or reboot the server. This feature helps organizations to keep operations running smoothly and reduce downtime even when there’s a need to increase memory capacity for applications and workloads.

Hot Add FAQ

What is Hot Add?

Hot Add is a feature that allows you to add hardware components, such as memory or CPUs, to a running virtual machine without any downtime. This makes it easier to scale and adjust resources as needed, without disrupting the operation of the virtual machine.

What are the benefits of using Hot Add?

Some benefits of using Hot Add include reduced downtime, increased flexibility, and improved resource management. By using Hot Add, you can allocate resources dynamically, ensuring that your virtual machines perform optimally and adapt to changing workload requirements.

Are there any prerequisites for using Hot Add?

Before using Hot Add, you should verify that your virtualization platform supports this feature and that it is enabled for the specific virtual machine(s). Additionally, the guest operating system within the virtual machine must be compatible with Hot Add functionality.

Are there any limitations when using Hot Add?

Yes, there can be some limitations when using Hot Add, depending on the virtualization platform and guest operating system. These may include the maximum amount of memory or CPUs that can be added, as well as possible performance impacts. It’s important to consult your platform’s documentation for specific details and limitations.

Can Hot Add be used with storage devices?

Hot Add can also be used with storage devices in some cases, such as adding a new virtual disk or expanding the size of an existing disk. However, this functionality may be limited depending on the virtualization platform and guest operating system, so it is crucial to consult the relevant documentation before attempting this.

Related Technology Terms

  • Hot Swap
  • Hot Plug
  • Dynamic Hardware Partitioning
  • Resource Allocation
  • Hardware Redundancy

Sources for More Information


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