Chapter 2

Understanding Virtualization in Cloud Computing

Virtualization is a powerful technology in cloud computing that allows for efficient resource management and flexibility. It involves creating virtual versions of physical resources like servers, storage, and networks. Let's break down the key concepts:

What is Virtualization?

At its core, virtualization is about creating a software-based (or "virtual") version of something physical. This concept isn't new—it dates back to the mainframe era. But today, it's a critical part of cloud computing. It allows for multiple operating systems and applications to run on the same hardware simultaneously, which optimizes hardware use and offers greater flexibility.

Benefits of Virtualization

• Cost-effective: It reduces the need for physical hardware, saving on capital expenses.
• Space-saving: Virtualization consolidates servers, reducing physical space requirements.
• Energy-saving: Fewer physical servers mean lower energy consumption.

Types of Virtualization in Cloud Computing

1. Application Virtualization: This enables remote access to applications from a server, allowing different versions of the same software to run concurrently.
2. Network Virtualization: Multiple virtual networks can coexist atop a single physical network, each with its own control and data plan, managed independently.
3. Desktop Virtualization: Users can remotely access their operating system from any location, making it easier to manage software installations and updates.
4. Storage Virtualization: Data from multiple sources can be managed and used as though it's from a single repository, improving storage management.
5. Server Virtualization: A physical server is divided into multiple virtual servers, each capable of running its own operating system and applications in isolation.
6. Data Virtualization: Data from various sources is compiled into a single, logical view, making it accessible remotely without the need for users to understand the underlying technical details.

Practical Uses of Virtualization

• Data Integration: Combining data from different sources for a unified view.
• Business Integration: Merging processes and operations from various business systems.
• Service-Oriented Architecture (SOA) Data Services: Providing data as a service in an SOA infrastructure.
• Organizational Data Search: Making it easier to find and access data across an organization.

The Role of Virtualization in Cloud Computing

Virtualization is key to delivering Infrastructure-as-a-Service (IaaS). It allows resources to be shared among multiple customers, making cloud services more scalable and cost-effective. It also plays a vital role in cloud migration, the process of moving applications and data to the cloud, which can lead to significant cost savings and operational efficiency.

Virtualization Tools and Products in Cloud Computing

Hypervisors (Virtualization Platforms)

• VMware vSphere/ESXi: A type 1 hypervisor that runs directly on the server hardware without requiring an additional underlying operating system.
• Microsoft Hyper-V: Available as a type 1 hypervisor called Hyper-V Server and a type 2 hypervisor as part of Windows OS. It supports the creation and management of virtual machines.
• KVM (Kernel-based Virtual Machine): An open-source type 1 hypervisor integrated into Linux OS that transforms Linux into a hypervisor.
• Xen: An open-source type 1 hypervisor that allows several guest operating systems to execute on the same computer hardware concurrently.

Desktop Virtualization

• VMware Workstation: A type 2 hypervisor used for creating and running virtual machines on a desktop or laptop for development, testing, or educational purposes.
• Oracle VirtualBox: A free and open-source hosted hypervisor for x86 virtualization, suitable for server, desktop, and embedded use.
• Microsoft Hyper-V (for Desktop): A type 2 hypervisor version included with Windows 10, allowing users to create and manage virtual machines on their personal computers.

Application Virtualization

• Docker: A platform as a service (PaaS) product that uses OS-level virtualization to deliver software in packages called containers.
• Podman: An open-source daemonless container engine for developing, managing, and running OCI Containers on your Linux System.

Network Virtualization

• Cisco ACI (Application Centric Infrastructure): A comprehensive SDN architecture that drastically lowers total cost of ownership, automates IT tasks, and accelerates data center application deployments.
• Open vSwitch: A production-quality, multilayer open source virtual switch that enables network automation while supporting standard management interfaces and protocols.

Cloud Management and Orchestration

• OpenStack: An open-source platform for cloud computing, mostly deployed as an infrastructure as a service (IaaS), whereby virtual servers and other resources are made available to customers.
• Apache CloudStack: An open-source cloud computing and IaaS platform that helps build, manage, and deploy cloud services by providing a comprehensive stack of features and components for cloud environments.

Backup and Disaster Recovery

• Veeam Backup & Replication: A backup and replication solution for virtual environments of any size, providing fast, flexible, and reliable recovery of virtualized applications and data.
• Unitrends: Provides business recovery and continuity solutions that enable adaptive recovery from virtual and physical system failures to all forms of disasters.

Monitoring and Management

• Nagios: An open-source computer-software application that monitors systems, networks, and infrastructure, offering monitoring and alerting services for servers, switches, applications, and services.
• vRealize Operations (formerly vCenter Operations Manager): A software product that delivers the quick operations management with intelligent operations from apps to storage for vSphere, Hyper-V, Amazon, and physical hardware.

Storage Virtualization

• DataCore SANsymphony: A software-defined storage platform that pools, replicates, and accelerates data across on-premises data centers, remote sites, and clouds.
• StarWind Virtual SAN: A software that eliminates any need for physical shared storage by simply mirroring internal hard disks and flash between hypervisor servers.

Understanding Cloud Virtualization and Migration

Cloud virtualization is all about abstraction, efficiency, and scalability. By creating virtual versions of computing resources, organizations can dynamically adjust to demand without physical constraints. Cloud migration takes this a step further by moving services to the cloud, which often translates to cost savings, scalability, and flexibility.

Implementing these technologies requires strategic planning and attention to detail, particularly around security, compliance, and application compatibility. The tools listed play a crucial role in facilitating a smooth transition to virtualized environments and cloud infrastructure.

Seven-Step Model of Cloud Migration

Cloud migration is the strategic process of moving data, applications, and other business elements to a cloud computing environment. A systematic approach to cloud migration is crucial for a smooth transition and involves the following steps:

Step 1: Assess Your Current Environment

Objective: Understand the performance, capacity, and compatibility of your current systems.

• Conduct a comprehensive review of your existing IT infrastructure, applications, and data.
• Identify dependencies that could impact migration and potential optimizations.
• Evaluate the technical and financial aspects to set realistic migration goals.

Step 2: Choose the Right Cloud Service Model

Objective: Find the cloud service model that best fits your organizational needs.

• Explore service models such as IaaS, PaaS, and SaaS, and determine which aligns with your business requirements.
• Consider public, private, and hybrid cloud solutions based on your security, control, and scalability needs.

Step 3: Select the Ideal Cloud Service Provider

Objective: Partner with a cloud provider that can meet your expectations and requirements.

• Evaluate providers like AWS, Microsoft Azure, or Google Cloud based on their services, reliability, compliance, and cost.
• Assess SLAs to understand the provider's commitment to performance and availability.

Step 4: Plan Your Migration Strategy

Objective: Develop a clear and detailed migration plan.

• Determine the migration approach: Rehosting, refactoring, or rearchitecting.
• Define roles and responsibilities to ensure clarity and accountability throughout the migration process.
• Set up a timeline and milestones for the migration.

Step 5: Data Migration and Application Transition

Objective: Move data and applications securely and efficiently to the cloud.

• Plan for data transfer with minimal disruption and ensure data integrity.
• Adapt or reconfigure applications for optimal performance in the new cloud environment.

Step 6: Monitor, Optimize, and Secure

Objective: Establish processes for ongoing management of your cloud environment.

• Implement continuous monitoring to track performance and usage patterns.
• Regularly update security measures to safeguard against evolving threats.
• Optimize resources to manage costs and maintain efficiency.

Step 7: Training and User Adoption

Objective: Ensure that your team is equipped to leverage the new cloud tools and workflows.

• Conduct training sessions to familiarize employees with the new cloud environment.
• Promote effective change management to support user adoption and minimize resistance.
• Gather feedback and iterate to refine processes and maximize cloud benefits.

Implementing Cloud Virtualization and Migration

Cloud Virtualization:

• Abstracts physical computing resources, creating a flexible and scalable virtual environment.
• Allows for dynamic allocation of server, storage, and network resources.
• Facilitates the creation of virtual machines and networks that mirror their physical counterparts.

Cloud Migration:

• Involves transferring on-premises applications, data, and workloads to the cloud.
• Enables organizations to tap into the cloud’s benefits like on-demand resources and potential cost reductions.
• Demands a robust strategy to tackle security, compliance, and application dependencies.

Key Considerations for Cloud Migration

• Ensure compatibility between your applications and the target cloud environment.
• Address legal and compliance issues, especially for data-sensitive industries.
• Plan for post-migration support and possible scenarios that could disrupt services.

Post-Migration: Harnessing Cloud Capabilities

Once the migration is completed, organizations can harness cloud capabilities for enhanced flexibility and efficiency in IT infrastructure management. Continuous optimization and iterative improvements are essential to exploit the full advantages of cloud computing fully. These steps, when followed diligently, pave the way for a successful cloud transformation journey.

Broad Approaches to Migrating into the Cloud

1. Re-hosting (Lift and Shift):

• Goal: Move applications to the cloud without changes.
• Best for: Organizations new to the cloud or with complex application code.
• Benefits: Immediate cost savings by reducing on-premise infrastructure.

2. Re-platform (Lift, Tweak, and Shift):

• Goal: Make minimal optimizations to the application for cloud compatibility without altering its core architecture.
• Best for: Companies taking a conservative approach to cloud adoption.
• Benefits: Improved system performance and some cloud efficiencies while maintaining familiarity with the application.

3. Revise (Re-architect):

• Goal: Modify the application significantly before moving it to the cloud to take full advantage of cloud-native features.
• Best for: Applications that need modernization to align with current business needs.
• Benefits: Enhanced agility, scalability, and performance.

4. Rebuild:

• Goal: Redesign the application from scratch using cloud-native technologies.
• Best for: When current applications are unable to meet business requirements.
• Benefits: Full utilization of the cloud capabilities, often leading to better agility, performance, and scale.

5. Replace:

• Goal: Switch out the existing application for a pre-built cloud solution (SaaS).
• Best for: When the cost or effort of rebuilding is unjustifiable.
• Benefits: Quick adoption, with new features and capabilities that were not previously available.

6. Retire:

• Goal: Decommission applications that are no longer useful.
• Best for: Streamlining and cost-saving by eliminating redundant apps.
• Benefits: Simplifies the IT portfolio and reduces costs by turning off unnecessary systems.

7. Retain (Do Nothing, for Now):

• Goal: Keep certain applications on-premise or in their current state.
• Best for: Applications that have recently been updated or don't have a clear business case for cloud migration.
• Benefits: No immediate change, providing time to plan strategically for a future migration or consider alternate solutions.
• Considerations: Certain regulatory, compliance, or technical constraints might necessitate retaining some applications. The cost and risk of moving certain applications may not justify immediate migration.

Overall Strategy Considerations:

When approaching cloud migration, it's essential to align the strategy with the organization's specific goals, capabilities, and requirements. The chosen approach should balance the benefits of cloud adoption with the readiness of the organization's applications and data for such a move.

Cloud Virtualization and Migration as Strategic IT Approaches

Cloud Virtualization:

• Involves the creation of virtual versions of physical computing resources, enabling greater agility and resource utilization.
• Facilitates workload mobility and disaster recovery.
• Enables a multi-tenant architecture, allowing for efficient resource sharing.

Cloud Migration:

• Refers to the relocation of data, applications, and workloads to a cloud computing environment.
• Empowers organizations with scalability, flexibility, and potentially significant cost savings.
• Involves strategic decision-making, including choosing the right model of cloud services (IaaS, PaaS, SaaS) and the type of cloud (public, private, hybrid, or multi-cloud).

Effective Planning for Cloud Migration:

• Incorporates understanding the technical and business impact, as well as the operational changes required.
• Requires robust security measures, governance policies, and compliance checks to be established.
• Demands regular performance monitoring and optimization to ensure the cloud environment meets the evolving needs of the business.

Why Use an Enterprise Cloud?

Adaptability and Specialization:

• The enterprise cloud caters to complex workloads and changing demands, ensuring that applications find their most suitable environments—public for scalability and innovation, private for control and security.

Unified Management:

• Despite the heterogeneous nature of the cloud environment, enterprise cloud platforms offer integrated management tools, simplifying oversight and governance.

Automated Operations:

• Deployment, scaling, and management of applications can be automated across various environments, enhancing efficiency and consistency.

Self-service and Flexibility:

• Empowers users with on-demand access to resources, allowing them to select and manage services according to their needs without unnecessary delays.

Who Uses an Enterprise Cloud?

Diverse Industries:

• Healthcare, retail, financial services, manufacturing, and government agencies are examples of sectors leveraging enterprise cloud platforms for improved outcomes and operational agility.

Components of Enterprise Cloud Management

1. Unified Governance:

• Policy-centric control across all cloud services, ensuring compliance and streamlined management.

2. Infrastructure and Platform Services:

• A mix of on-premises and public cloud offerings that provide flexible infrastructure for applications of any scale.

3. Zero-click Operations:

• Advanced automation and machine learning drive operational simplicity, requiring minimal manual intervention.

4. Elastic Consumption:

• Businesses only pay for the IT resources they use, with the ability to scale seamlessly in response to growing demands.

5. Integrated Security:

• Across private and public clouds, security is automated to maintain standards and adapt to emerging threats.

Benefits of an Enterprise Cloud Strategy

1. Economic Flexibility:

• Shifting from capital-intensive IT models to a variable, pay-as-you-go approach that mimics public cloud economics.

2. User-centric Design:

• Constantly evolving services to meet the demands of end-users for innovation and quality.

3. Agile IT Response:

• Competing with the speed of cloud providers by offering instant infrastructure provisioning and scaling.

4. Business-centric IT:

• Allocating more resources to strategic initiatives that contribute to revenue generation rather than just operational maintenance.

5. Freedom of Choice:

• Avoiding vendor lock-in with the flexibility to run workloads on the most appropriate cloud platform.

Elements of an Enterprise Cloud Strategy

1. Public Cloud:

• Services like AWS, Azure, and GCP provide on-demand computing resources, billed based on usage.

2. Private Cloud:

• Offers cloud-computing services on proprietary infrastructure, delivering cloud-like flexibility with added control and security.

3. Hybrid Cloud:

• Integrates public and private cloud infrastructures, enabling applications to operate across both with greater flexibility and optimization.

4. Multi-Cloud:

• Utilizes multiple cloud computing and storage services in a single architecture, allowing for best-of-breed solutions from various cloud providers.

Enterprise Cloud Storage Considerations

1. Scalability and Capacity:

• Planning for current and future storage needs, allowing for expansion as data grows.

2. Performance Alignment:

• Matching storage performance with the application requirements and service level agreements.

3. Tiered Storage:

• Utilizing various storage tiers to balance cost and performance, aligning each workload with the appropriate storage solution.

4. Security Measures:

• Ensuring all stored data, across all forms and locations, is protected against unauthorized access and threats.

5. Disaster Recovery:

• Establishing robust backup and failover systems to maintain continuity in the face of outages or disasters.

Cloud Virtualization and Migration in the Enterprise Cloud

Cloud Virtualization:

• Abstracts physical resources, enabling virtual environments for dynamic resource allocation and increased utilization.

Cloud Migration:

• Involves moving applications, data, and workloads to the cloud to benefit from scalability, cost savings, and operational flexibility.

Key Integration:

• Both processes are central to modern IT operations, helping to optimize resources and adopt cloud services efficiently.

Planning for a Successful Enterprise Cloud Implementation

1. Security and Compliance:

• Ensuring all cloud activities adhere to regulatory requirements and protect sensitive data.

2. Application Dependencies:

• Assessing and planning for dependencies to ensure seamless application performance in the cloud.

3. Strategic Resource Management:

• Allocating IT resources to align with business priorities and revenue-generating activities.