Command Central renames the old product installation directory, then uses the old directory name for the new product installation.

Benefits: Simple; similar to overinstall in that all paths, hosts, and ports remain the same. Can fully automate using custom composite templates.

Cautions: Risky; rollback is complicated. Significant downtime. Must back up live databases; use of cloned databases is not supported. Requires double disk space because old installation is still present. Requires extensive automated testing before production environments can be migrated.

Benefits: New installation is almost identical to old. Safer than first scenario; rollback is much simpler. Can start old installation after shutting down new installation, and vice versa. Can fully automate using custom composite templates or can perform step by step using a combination of the Command Central Web user interface and commands.

Cautions: Requires double disk space because old installation is still present. Must adjust third-party tooling to point to new installation directory.

Benefits: Safer than first scenario; rollback is much simpler. Downtime is less than first and second scenarios; can migrate gradually while old installation continues to operate. Can fully automate using custom composite templates.

Cautions: Preparation for migration is more complex than first and second scenarios. Requires double disk space because old installation is still present. Must change endpoints to reflect new ports. Must adjust third-party tooling to new installation.

Typically required because of upgrades to hardware and operating systems. Use of same installation directory and ports can minimize change. Use of DNS to control IP-to-host mapping for the old and new environment can greatly simplify impact on external clients.

Benefits: Safest scenario, and minimal downtime. Easiest scenario when environment runs in a private or public cloud that allows temporary increase of capacity to host new environment and then release resources used by old environment. Can phase migration. Must adjust third-party tooling to new installation. Can fully automate using custom composite templates or can perform step by step using a combination of the Command Central Web user interface and commands.

Cautions: Some products allow cross-operating system migration, but for other products, this type of migration might have unpredictable results, especially when old machine is Windows and new machine is non-Windows, or vice versa.