Logic, then Physics
Logic, then physics
Relocations can be achieved in a number of ways and often employ a combination of the following three methods:
Method No. 1: The lift and shift
The simplest, the lift and shift, involves taking a verified, successful backup of a system, powering it down, moving it and powering it back up.
Method No. 2: The swing move
Another, more complex method is the swing move. This method entails setting up temporary systems at the target site and replicating data to those systems in order to shift an application or service to the target site quickly-and then powering down and relocating the equipment from the source site.
The temporary equipment is retired once the service or application is again running on its original equipment. This method is commonly used when the time it takes to physically relocate a system exceeds the organization's tolerance for downtime of the application or service.
Method No. 3: The logical move
Another method that is gaining widespread popularity is the logical move, which does not involve physically relocating any assets. Logical moves are used for existing virtual machines or as an opportunity to migrate physical systems to virtual platforms. Many organizations find that data center relocation creates opportunities to gain increased efficiencies such as those that come from consolidating physical systems.
Moves of this type involve setting up platforms to host VMs at the target data center, performing Physical-to-Virtual (P2V) migrations at the source site, and transferring those virtual instances to the target site over high-speed links. The VMs are then started at the target site and users are pointed to the applications and services running at the target site.
Regardless of the method employed, an organization must always go through the exercise of defining the logical components of each service and application. It must map those components back to physical devices. This process, commonly referred to as application bundling, allows the relocation planners to develop a picture and logical sequence of events that must take place in order to move an application or service. It also helps to flesh out the logical and physical dependencies that applications and services have on one another.