The core purpose of virtualization is to enable a computing environment to run multiple independent systems at the same time. Virtualization simplifies data center management and increases workload density to use more of the computing capacity of servers.
Virtualization reduces costs through the sharing of hardware, infrastructure, and administration. Benefits include the following:
Increasing the utilization of hardware
Enabling greater flexibility in resource allocation
Reducing data center power requirements
Minimizing management costs
Lowering the cost of ownership
Providing administrative and resource boundaries between applications on a system
Quickly provisioning virtual compute environments from templates and clones
Providing layered security and isolation
Oracle Solaris 11.4 enables you to take advantage of several virtualization technology models to suit your data center requirements.
The virtualization models are described by means of the following competing characteristics:
The amount of execution environment isolation
The amount of resource flexibility
The more isolation that a model provides, the less resource flexibility it provides. The more resource flexibility that a model provides, the less isolation it provides. Because these characteristics compete, they cannot be maximized by a single model.
You can use the Oracle Solaris 11.4 operating system with one or more of the following virtualization technologies, listed in order of increasing execution isolation and decreasing resource flexibility:
Operating system virtualization provides one or more isolated execution environments in a single operating system instance. Each environment contains what appears to be a private copy of the operating system in a container. The operating system virtualization model provides near-native performance and flexibility, and has a much smaller disk, RAM, and CPU footprint than either virtual machines or physical domains. However, the operating system virtualization model provides the least amount of execution environment isolation.
Oracle Solaris 11.4 provides this virtualization model by means of the Oracle Solaris Zones feature.
Virtual machines can be used to run multiple operating system instances with a single set of hardware resources. Each virtual machine that you create runs its own operating system. You can run various operating systems in this way. A software or firmware hypervisor creates the illusion that each guest operating system instance is running on its own separate system. Virtual machines provide less resource flexibility than a machine that uses operating system virtualization, but virtual machines do provide more isolation.
Oracle Solaris 11.4 provides this virtualization model by means of Oracle VM Server for SPARC, Oracle VM Server for x86, and Oracle VM VirtualBox. Note that running Oracle VM VirtualBox and Oracle Solaris Kernel Zones on the Oracle Solaris x86 system at the same time is not supported.
For information about using Oracle VM VirtualBox, see the Oracle VM VirtualBox documentation (https://www.virtualbox.org/wiki/Documentation).
Hardware partitions, also known as physical domains, provide physical separation between the running operating system and its separate set of resources and power. Because this model does not use a hypervisor, it provides bare-metal performance. This virtualization model provides the most isolation, but it is much less flexible with resource configuration than either the virtual machines or operating system virtualization model.
Oracle provides this type of virtualization on Oracle's SPARC M-Series servers. For more information, see the Oracle SPARC Servers: Systems Documentation (https://www.oracle.com/technetwork/server-storage/sun-sparc-enterprise/documentation/index.html).
The following sections describe two levels of virtualization to consider:
Compute virtualization – Virtualization at the operating system and physical domain level
Network virtualization – Virtualization at the networking subsystem level
You can use one or more virtualization technologies to maximize workload density. For example, you could configure multiple zones to run within Oracle VM Server for SPARC logical domains in one or more physical domains of a SPARC M-Series system to leverage the strengths of the different virtualization technologies.
Figure 1 Using Oracle Solaris Virtualization Technology in Your Environment
Oracle Solaris 11.4 virtualization technologies provide a different emphasis in the degree of isolation of each instance of the operating system versus flexibility. More isolation leads to less sharing of system resources.
Physical domains on Oracle SPARC M-Series servers let you deploy different Oracle Solaris operating systems to electrically isolated domains. Each domain provides separation and isolation from the other domains on the M-Series server at the socket level, or at the board level to provide electrical isolation. Each domain can run a different version of the Oracle Solaris operating system that is supported by the hardware.
Oracle VM VirtualBox helps you develop and test software in heterogeneous environments. Oracle VM VirtualBox enables you to run unmodified 32-bit and 64-bit operating systems as virtual machines on Intel and AMD processors directly on your existing operating system.
Oracle VM Server for x86 enables you to deploy a server with heterogeneous operating systems, including supported versions of the Oracle Solaris operating system as guests.
Oracle VM Server for SPARC enables you to migrate Solaris 8, Solaris 9, Oracle Solaris 10, and Oracle Solaris SPARC workloads and to deploy different Oracle Solaris environments on supported SPARC T-Series and SPARC M-Series systems.
Oracle Solaris Kernel Zones can run many instances per host to share system resources but still provide independence of the kernel zone from the global zone and the host itself. This configuration enables you to run multiple versions of Oracle Solaris and provides enhanced security to the operating system instances and its applications.
Oracle Solaris Zones shares the kernel among the instances to maximize the efficiency and scalability of workloads and to migrate Oracle Solaris 11 and Oracle Solaris 11.4 workloads.
Figure 2 Virtualization Products
The Oracle Solaris 11.4 operating system provides support for several of the following network virtualization features, some of which implement new IEEE standards:
Using OSI stack features such as aggregations, edge virtual bridging, data center bridging, flows, tunnels, and VXLANs. See Chapter 1, Summary of Oracle Solaris Network Administration in Strategies for Network Administration in Oracle Solaris 11.4.
Using a virtual NIC as a data link layer network device to enhance management efficiency, abstraction, and the performance of networked objects between multiple zones and logical domains. See Configuring the Components of a Virtual Network in Managing Network Virtualization and Network Resources in Oracle Solaris 11.4.
Managing network devices that support the single root I/O virtualization (SR-IOV) feature. See Using Single Root I/O Virtualization With VNICs in Managing Network Virtualization and Network Resources in Oracle Solaris 11.4.
Using an elastic virtual switch as a distributed virtual switch to expand network virtualization capabilities by enabling you to manage virtual switches across multiple systems. Elastic virtual switches enable you to deploy virtual networks that span multiple hosts within either a multi-tenant cloud environment or a data center. See Chapter 6, Administering Elastic Virtual Switches in Managing Network Virtualization and Network Resources in Oracle Solaris 11.4.