vSphere is a sophisticated product with multiple components to upgrade. Understanding the required sequence of tasks is vital for a successful vSphere upgrade.

Figure 1. Overview of vSphere Upgrade Tasks
High-Level Overview of vSphere Upgrade Tasks

Upgrading vSphere includes the following tasks:

  1. Read the vSphere release notes.
  2. Verify that you have backed up your configuration.
  3. If your vSphere system includes VMware solutions or plug-ins, verify that they are compatible with the vCenter Server appliance version to which you are upgrading. See VMware Product Interoperability Matrix at http://www.vmware.com/resources/compatibility/sim/interop_matrix.php.
  4. Upgrade vCenter Server.

    See Overview of the vCenter Server Upgrade Process.

  5. To ensure sufficient disk storage for log files, consider setting up a syslog server for remote logging. Setting up logging on a remote host is especially important for hosts with a limited amount of local storage.

    For detailed instructions, see ESXi Upgrade.

  6. Upgrade your VMs manually or by using vSphere Lifecycle Manager to perform an orchestrated upgrade.

    For detailed instructions, see Installing and Administering VMware vSphere Update Manager.

When you upgrade vSphere, you must perform all procedures in the specified sequence to avoid possible data loss and to minimize downtime. You can perform the upgrade process for each component in only one direction. For example, after you upgrade to vCenter Server 7.0, you cannot revert to vCenter Server 6.5 or 6.7. With backups and some planning, however, you can restore your original vCenter Server environment.