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Oracle VM templates are prebuilt, preconfigured and production-ready, enabling IT administrators to deploy template-based VMs to their Oracle VM environments. The templates can help simplify deployments throughout the application lifecycle, leading to lower costs and quicker implementations.
Oracle packages the templates using its own best practices and standards, and admins can download the templates and try them out for free, with the option to purchase the product licenses if they like what they see. Each template provides a baseline that admins can use repeatedly to create deployable VMs. The VMs inherit the template's contents and configurations, and admins can also enhance and tune VMs to meet specific workload requirements.
A typical Oracle template includes a guest OS and application software, along with basic configuration information such as the number of virtual CPUs, amount of memory, virtual disk size and any other settings necessary to support the VM deployment.
Oracle also offers Oracle VM Virtual Appliances, a similar preconfigured package. The appliances are sometimes confused with Oracle VM templates because Oracle documentation occasionally uses the term template to refer to both product types. The main difference between them is that Oracle packages templates as compressed .tgz files and appliances as .ovf files or .ova files.
Acquire Oracle VM templates
Oracle offers templates for a number of technologies, such as Oracle Solaris and Fusion Middleware. For example, Oracle provides a set of templates that support Oracle Database deployments, including Single Instance and Real Application Clusters (RAC). Oracle configures the templates with a minimal installation of Oracle Linux 6 or 7, along with a database system. Oracle claims that even novice admins can install a single Oracle Database instance in minutes or a production-ready RAC configuration in a few hours.
Admins can download Oracle VM templates from the Oracle Technology Network, and then use Oracle VM Manager to import them into the Oracle VM environment. Admins can also clone an existing VM or template in VM Manager, a feature they can use in conjunction with Oracle VM templates.
For example, admins might import and clone an Oracle E-Business Suite template, install additional applications on the new template and use it to create a specific type of VM. And admins can continue to create VMs based on the original template.
Deploy Oracle VM templates
Before admins set up Oracle VM templates, they must install Oracle VM, which provides a secure, scalable environment for virtualizing business applications. Oracle has engineered Oracle VMs specifically to support tier-1, data-driven applications throughout their lifecycles, from development and testing to production and ongoing maintenance.
After admins install an Oracle VM, they must add at least one instance of Oracle VM Server. The server comes with a hypervisor and privileged control domain known as Domain 0 (Dom0), which runs a minimized Oracle Linux Unbreakable Enterprise Kernel. Admins can install the server directly on bare metal without requiring a host OS. The hypervisor controls privileged access for all guests to the Dom0 kernel and device drivers.
Admins must also install Oracle VM Manager, a centralized management tool for controlling the Oracle VM environment and its components, including Oracle VM templates. Oracle recommends that admins install Oracle VM Manager on a separate machine from the Oracle VM Server instances to avoid a single point of failure.
Before admins can use Oracle VM templates, they must create a repository for storing them and other Oracle VM resources. Admins can use Oracle VM Manager to import templates and make them available to the storage pool. Admins must also perform several network-related tasks, such as creating a VM network and generating a set of virtual network interface cards.
Once the templates are available in the storage pool, admins can create VMs by cloning -- or copying -- the original templates. Oracle VM Manager provides a VM creation wizard that walks admins through the necessary steps. However, the cloning process can take some time depending on template size or storage performance.
After admins create a VM, they will likely need to update several configuration settings when launching the VM. For example, if admins create a template that contains an instance of Oracle Database, they must provide system account passwords, as well as the TCP/IP port for Oracle Net Listener. Oracle recommends that for any VMs based on Oracle VM templates, admins should change the default usernames and passwords to minimize security risks.