A systems administrator is deploying a new version of a website. The website is deployed in the cloud using a VM cluster. The administrator must then deploy the new version into one VM first. After a

A canary deployment routes a small percentage of live traffic to the new version simultaneously alongside the old, rather than updating VMs sequentially until all are replaced.

Blue-green deployment maintains two identical environments and switches all traffic at once via a load balancer cutover, not an incremental per-VM update process.

A rolling upgrade sequentially updates each VM, pausing to verify stability before moving to the next instance. This matches the described process of updating one VM, monitoring for issues, then repeating through the cluster. The strategy limits the blast radius of any defect by ensuring only a subset of VMs runs the new version at any given time.

Staging is a pre-production environment used for testing before any production release, not a production upgrade method.