Low Cost, High Efficiency: A Brief Analysis of the Advantages and Characteristics of Server Virtualization
Virtual machine technology, hailed as a technology that could change the world in the future, has its advantages and characteristics. This article will give you an overview of virtualization and how to apply it according to the importance level of application systems. It will help enterprises solve server consolidation and upgrade issues using virtual machine technology while ensuring system and data security. It also addresses system security concerns at a low cost and ensures continuous and reliable operation of business systems.
1. Development of Virtualization
(1) Virtualization Technology. Virtualization software can realistically simulate computer hardware environments and directly use host devices such as keyboards, mice, network cards, CD-ROMs, floppy drives, etc., for interaction and communication with external environments. Currently, virtualization technology has been applied in various fields, including server virtualization, CPU virtualization, storage virtualization, and now desktop virtualization.
In virtualization, the computer running virtual computer software is called the host (Host), and the virtual computer running on the virtual machine software is referred to as the guest (Guest). A virtual machine (VM) is a system that allows multiple operating systems to run concurrently on a single physical server, providing more efficient use of underlying hardware. In a virtual machine, the central processing unit chip isolates a segment of storage from other parts of the system, allowing the operating system and applications to run in a "protected mode" environment.
One benefit of using virtualization technology is that if a program freezes in one virtual machine, it won't affect the normal operation of programs and the operating system outside the virtual machine.
(2) Virtualization Products. The first generation of virtualization products provided server partitioning capabilities through a hypervisor or host architecture. The second generation of virtualization technology added virtualization management, productivity planning, physical server to virtual machine migration, and other tools for consolidating production servers. VMware's third-generation virtual architecture (VI3) represents the next generation of virtualization technology. This virtual architecture redefines a new IT benchmark by integrating industrial standard servers and storage into a unified, dynamically manageable resource pool, keeping any application or operating system continuously optimized and highly available. It empowers enterprises to transform, manage, and optimize their IT system architectures.
(3) Purpose of Virtual Servers. A virtual server merely simulates the behavior and capabilities of an independent computer using software. At the bottom of the server virtualization software stack is a regular operating system installed directly on the server hardware. Above it is a virtual layer responsible for redirection and simulation, which constitutes the virtual computer. Together, these two layers are called the host.
Server Virtual Architecture Technology
Using server virtual architecture solutions can better address the drawbacks of traditional single-physical-server deployment methods. This solution significantly improves server consolidation efficiency, greatly simplifies server cluster management complexity, enhances overall system availability, and significantly reduces investment costs. It offers excellent technical leadership and cost-effectiveness. By encapsulating traditional server application environments into portable archive files, it enables continuous business operations and reduces total system costs, making it very suitable for rapidly developing application areas like broadband.
Business Continuity Solutions
Successful elements of a business continuity strategy include: application availability planning; preventive measures including monitoring and platform redundancy; data protection; disaster recovery strategies; effective personnel planning. Using a virtual architecture, IT administrators can improve all aspects of business continuity, such as: faster and less expensive disaster recovery due to hardware independence between primary and backup servers; eliminating planned hardware downtime and significantly reducing planned software downtime; single-point control technology managing all virtual machines and monitoring the host; fully compressing the host into a file for capture and recovery; simplified and repeatable automated procedures.
(1) Simplification of Cluster Redundancy Based on Virtual Machines. Enterprises use middleware like Microsoft and Veritas cluster software to bind two servers in a hot standby environment. As a result, businesses do not need to double the manpower and resources required for hardware quantity, management, or patch installation, achieving high availability. Even if the applications running on the server have cluster awareness, such arrangements can still lead to non-application failures in case of hardware or software errors on the main server. Redundancy eliminates single points of failure.
With virtualization, IT administrators can create clusters on both physical machines running critical applications and equally configured virtual machines. In standby mode, virtual machines do not consume computing resources and can be highly consolidated onto one or a few physical platforms. The redundancy ratio changes from 2N to N+1. Physical-to-virtual clustering supports the same cluster software as physical-to-physical clustering. Meanwhile, saved costs enable higher availability for more loads and allow signing more high-level service agreements.
(2) Data Recovery Without Original Hardware. Most enterprise IT departments use common backup software such as Tivoli Storage Manager, Legato Networker, or Veritas NetBackup to create data and application backups. Since backup strategies protect against user errors and certain hardware/software failures, longer recovery times and multiple recovery points are acceptable. However, enterprises must ensure that data can indeed be recovered.
IT administrators need to provide a test failover server for each backed-up host, install the operating system, install the backup agent, and attempt to adjust the Windows registry and other system configurations on the test failover server. If system adjustments succeed, the backup server and backup agent can be used to test data recovery. Operating system installation, backup agent installation, and Windows registry adjustments need only be done once. Service period virtual architecture ensures that enterprises: eliminate hardware resource barriers for post-disaster testing and recovery; avoid installing systems and backup agents by using virtual machine templates to shorten recovery cycles; make disaster recovery more reliable and repeatable with standardized virtualized hardware.
Since the virtual machine built by virtual machine software is just a VHD file in a real physical computer, performing all operations within each virtual machine environment does not affect the host environment. Two or more virtual machines can mutually provide hot standby functions, enabling automatic switching when there is a server power failure, automatic switching when the server's hard drive, CPU, RAM fails, automatic switching when network connections fail (such as NIC or network cable failures), and automatic switching when the operating system, database, or application fails. Manual switching functionality should be provided so that system administrators can perform manual switching when the host load is too high or at other appropriate times. Multiple safe switches can be completed.
(3) Integration and Automation of Failover Servers. For deployments of critical applications associated with a storage area network (SAN), an enterprise's disaster recovery strategy typically includes a hot site for disaster recovery with complete data replication between the primary and backup sites. This strategy provides minimal recovery point objectives (RPO). However, considering recovery time objectives (RTO), the recovery time heavily depends on the ability to recover physical servers, operating systems, system parameters, and applications beyond data recovery.
To maintain minimal recovery time objectives (RTO), the same hardware and system configuration needs to be maintained at the failover site. Such a configuration is costly both during the initial capital investment phase and during project operation, upgrades, maintenance, and support phases. An obvious drawback of this solution is the pre-provisioning of too many new servers and usually no possibility of adjusting the Windows registry for data recovery and configuring other system parameters for different failover servers.
The deployment of a virtual architecture across the entire enterprise ensures that the enterprise avoids stagnation at the failover site, reduces investment costs from the perspective of server consolidation at both the primary and backup sites, automates the recovery process, and integrates storage management software, improving the reliability of the recovery process.
Advantages of Server Virtualization Solutions
(1) Cost Reduction. Through server consolidation, controlling and reducing the number of physical servers significantly improves the resource utilization of each physical server and its CPU, thereby reducing hardware costs; reducing operational and maintenance costs, including data center space, cabinets, network cables, electricity consumption, air conditioning, and labor costs.
(2) High Operational Efficiency. Accelerates the deployment of new servers and applications, greatly reducing server rebuild and application loading times; proactively plans resource growth ahead of time, responding quickly to customer and application needs without requiring a long procurement process followed by trial runs; hardware maintenance that previously required days/weeks of change management preparation and 1-3 hour maintenance windows can now be performed quickly for hardware maintenance and upgrades.
(3) Service Level. Helps your company establish a relationship between business and IT resources, aligning IT and business priorities, managing all servers as large resources uniformly, and allocating resources as needed; protecting investments in old hardware and operating systems; no longer worrying about compatibility, maintenance, and upgrades of old systems.
(4) Future Centralized Network Storage Possibilities. Due to cost or other reasons, servers not connected to a storage network (SAN, iSCSI, NAS) can be considered after consolidation since the number of physical servers decreases. This fully utilizes the advantages of network storage, centrally managing and backing up dispersed data, laying the foundation for future disaster recovery for these servers and applications. At the same time, through the unique functions of virtual machines and the effective combination of network storage, application availability, mobility, and flexibility are improved.
Summary
Virtualization technology represents a significant advancement in the construction and management of enterprise IT infrastructure, reducing the cost of informatization and providing users with better service levels. Through server consolidation, it controls and reduces the number of physical servers, increases the resource utilization of each physical server and its CPU, lowers hardware procurement costs, operational and maintenance costs, enables quick hardware maintenance and upgrades, and addresses system compatibility issues.
[Link to Source] http://www.xwkj.com/