Once an Oracle VM Server is installed and discovered, an administrator has no need to directly access the system unless directed to do so by Oracle Support. All maintenance and configuration is handled directly from the Oracle VM Manager instance that has ownership of the server. This makes system administration such as performing server updates, configuring networks, attaching storage, configuring clustering and the management of virtual machines much easier for a systems administrator and reduces the security implications of provisioning access to multiple systems within a deployment.
Oracle VM Manager is able to communicate directly with each Oracle VM Server via the Oracle VM Agent installed and running on the server. Communications are secured using TLS and authentication against the Oracle VM Agent is required. The password used for the Oracle VM Agent is configured at install time, and is required by Oracle VM Manager to perform server discovery. Once Oracle VM Manager has taken ownership of the Oracle VM Server, authentication of the Oracle VM Manager against the Oracle VM Agent is achieved using certificates to improve the security of the Oracle VM Agent. This ensures that only the Oracle VM Manager that has ownership of an Oracle VM Server is authorized to perform any action on the server. The Oracle VM Agent is responsible for performing all configuration changes and maintenance initiated from the Oracle VM Manager.
Oracle VM Server software updates and upgrades are handled by configuring one or more server update repositories for the Oracle VM Servers from within Oracle VM Manager. One or more update repositories can be configured for x86-based Oracle VM Servers, or for SPARC-based servers. These repositories are available to all Oracle VM Servers with that hypervisor type. You can also override these repositories at the server pool level. When a repository has been configured, Oracle VM Manager reports whether or not updates are available for each Oracle VM Server in the environment. Updating a server can be triggered from Oracle VM Manager. See Update Server in the Oracle VM Manager User's Guide for more information about Oracle VM Server updates.
During an update, the Oracle VM Server is put into maintenance mode. If the server is part of a clustered server pool, any virtual machines running on the server are automatically migrated to an alternate server within the server pool. The update is performed without affecting existing services. If the server requires a reboot after an upgrade, this is performed automatically. Once the server has rebooted, it rejoins the cluster and resumes its normal functions. See Edit Server in the Oracle VM Manager User's Guide for more information about maintenance mode.
Additional networking configuration is also handled from within Oracle VM Manager. During installation, a primary network is defined to allow the server to connect to the Server Management network. From this point onward, any further network configuration is performed from within Oracle VM Manager. Networking for Oracle VM is described in more detail in Chapter 5, Understanding Networks.
The process of defining Storage Connections and mount points is also handled from within Oracle VM Manager. These connections and how they are created are discussed in more detail in Chapter 3, Understanding Storage.
It should be clear that other than the initial installation required for an Oracle VM Server, all administrative tasks related to server maintenance and configuration are handled by Oracle VM Manager. This centralized administration not only eases the management of servers, but also improves security and reduces the likelihood of configuration errors that could result in server downtime.