What is meant by Virtualization?
Virtualization enables a single computer to perform the duties of several computers by sharing the resources of a single hardware across various settings.
What is meant by FT in virtualization?
- FT often stands for “Fault Tolerance” in virtualization.
- Fault Tolerance, often known as FT in virtualization, is a feature created to provide high availability and minimize downtime for virtual machines.
- A virtual machine is hosted on a physical server or host that offers the resources required for it to function when it is running in a virtualized environment.
- In a solution without fault tolerance, if the actual host fails, the virtual machine it is hosting would also fail, causing downtime and even compromising data.
- Virtualization companies like VMware and Hyper-V have created fault-tolerant solutions that duplicate the virtual machine on a new physical host in order to solve this problem.
- In order to maintain the availability of the VM's services and prevent data loss, this redundant copy continuously mimics the state of the primary VM and assumes control right away in the event of a host failure.
- Two virtual computers run simultaneously in a fault-tolerant configuration, but only one is ever actively running at once: the other serves as a backup.
- The standby VM continuously checks the status of the active VM and makes sure that its state is current while the active VM processes all requests and transactions.
- The “record and replay” mechanism used by FT keeps the active and standby VMs in sync by recording all the commands issued by the current VM and sending them to the standby VM.
- To make sure that its state is always the same as the active VM's state, the standby VM replays these instructions.
- The standby VM can take over without any interruption or data loss if the active VM fails in this fashion.
Fault tolerance implementation
- Fault tolerance implementation, such as CPU and memory, as well as network bandwidth to maintain the synchronization of the active and standby VM
- However, not all virtual machines are compatible with fault-tolerant architectures (FT), as they could make use of hardware features that are not supported in such architectures.
- In order to achieve high availability and prevent downtime, FT in virtualization produces a redundant duplicate of a virtual machine on a different physical host.
- This is accomplished by continuously mirroring the state of the primary VM to a standby VM, which assumes control right away in the event of a host failure, preserving business continuity and preventing data loss.
What is meant by HA in virtualization?
HA stands for High Availability.
High availability in virtualization refers to the ability of a virtualized environment to continue functioning even in the event of a hardware or software failure. Essentially, it means that if one physical server in a cluster goes down, the virtual machines (VMs) running on that server can be automatically migrated to another available server in the cluster without any noticeable downtime.
To achieve high availability, virtualization platforms like VMware, Microsoft Hyper-V, and KVM use technologies such as clustering, live migration, and fault tolerance. Clustered servers work together as a single entity, allowing the virtual machines to be moved seamlessly between them as needed. Live migration allows virtual machines to be moved from one host to another while they are still running, ensuring continuous availability.
Fault tolerance provides redundancy by creating a duplicate copy of a virtual machine on another host, so if one host fails, the duplicate VM can take over seamlessly.
High availability is essential in virtualized environments where downtime can have a significant impact on business operations. It helps ensure that critical applications and services remain available to users even in the face of hardware or software failures.