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What is virtualization?

Migration to VMware
Migration to VMware

Virtualization refers to the provision of physical hardware resources for virtual machines. It is possible for one or multiple, separate guest systems.

The guest system ("VMs" for virtual machines) do not know of their
virtual existence and behave the same way "real" servers would.

With VMware ESXi it is possible to create virtual machines instead of operating a physical server for each application. This increases efficiency. The fact that multiple applications can be made available on a single host system can save a lot of physical hardware. Existing physical machines with all their data and settings can be converted into virtual machines.

In this way, the existing server farm can be reduced to a minimum of physical servers, which also lowers operating costs. VMware can help reduce the existing server farm and the associated operating coststo a minimum.

VMware ESXi Basics

ESXi is a virtualization solution from VMware. It fundamentally changes the management of the IT-infrastructure.

With VMware hardware resources can be allocated much more efficiently and much faster. Hardware is used more efficiently as applications only receive the hardware resources they actually need. Administration of VMware is also very user friendly and virtual machines can be backed up comfortably using backup software from Veeam.

The availability of applications can be maximized with features like vMotion, High Availability (HA) and Fault Tolerance (FA). At the same time, VMware ESXi is significantly more cost-effective and easier-to-use than conventional IT-solutions.



VMware Basics

vCenter Server

vCenter Server management
vCenter Server management

vCenter Server simplifies the management of virtualization environments:

One single administrator can manage 100+ workloads and maximizes productivity compared to the management of physical infrastructures.

vCenter Server is the simpliest and most efficient way to manage ESXi centrally, wether there are only a few or many thousand virtual machines.

vCenter Server offers:

  • Simple and central management of all hosts and virtual machines
  • Performance monitoring of cluster, hosts and virtual machines
  • Detailed information about the status and the configuration of clusters, hosts, virtual machines, storage, the guest operating system and other critical components of the virtual infrastructure

vCenter server is required for the use of vMotion, DRS and HA.




Moving a virtual machine
Moving a virtual machine

With vMotion virtual machines can be migrated from one physical server to another during operation, without the user noticing this migration.

No application has to be stopped and no operating-system has to be shut down.

Advantages and features:

    • Hardware maintenance without down time and interruption of the ongoing business
    • Migration of virtual machines away from servers with malfunction or insufficient performance
    • Implementation of uninterrupted live migration that is unnoticed by the user
    • Continuous and automatic provisioning of virtual machines within resource pools
    • Parallel execution of multiple migrations - to continuously optimize a virtual IT-environment
    • Identification of the ideal position for a virtual machine within seconds: with a migration assistant that provides real-time information about availability
    • Migration of any virtual machine regardless of the implemented operating system across any hardware and storage type supported by VMware ESXi (such as Fibre-Channel-SAN, NAS and iSCSI)
    • Allocation of priorities for live-migrations - to ensure that mission-critical virtual machines get access to the requires resources
    • Scheduling of migrations at predefined times and without additional input from the administrator
    • Use and update of a check list with a detailed register of the migrations

      High Availibility (HA)


      VMware HA offers consistent, cost effective failover protection in case of hardware- or OS failure in a virtualized IT-environment.

      Advantages and features:

      • Virtual machines are monitored constantly to detect OS-and hardware failures in time
      • In the case of a server loss the affected virtual machines are automatically restarted on another physical server within the resource pool
      • To protect the applications virtual servers will be automatically restarted in case of a failure detection

      High Availability provides:

      • Consistent protection in case of server and operating system failures for all applications, independent of the type of server hardware or the operating system of the virtual machines
      • High availability and protection for applications which otherwise would not have protecting functions

      Fault Tolerance (FT)

      Fault Tolerance is based on the vLockstep-technology, and offers consistent data availability without downtime or data loss for all applications.

      Advantages and features:

      • Seamless failover with status preservation:
        In case of failure of protected virtual machines, a failover with status preservation automatically takes place, so there is no down times and no data-loss, and uninterrupted availability is ensured
      • Automatic creation of secondary virtual machines:
        After the failover a secondary virtual machine is automatically created to ensure the continuous protection of the applications
      • Compatibility with all shared storage types:
        Fault Tolerance supports all types of shared storage (Fibre Channel, NAS, iSCSI)
      • Compatibility all operating systems:
        Fault Tolerance supports all ESXi-compatible operating systems
      • Compatibility with existing DRS- and HA-cluster:
        Fault Tolerance supports existing DRS- and HA-clusters via an additional dedicated network (depending on the size of the virtual environment, 1 or 10 Gbps)
      • Simple administration via point-and-click:
        Fault Tolerance is activated and deactivated in the vSphere Client by simple point-and-click