Canary deploys: When using canary deploys, all users are routed to the old version, except for a group of selected test users who are routed to the new version. When the test users have approved the new version, regular users can be routed to the new version using a blue/green deploy.

Blue/green deploys: Traditionally, a blue/green deploy means that all users are switched to either the blue or the green version, one being the new version and the other being the old version. If something goes wrong when switching over to the new version, it is very simple to switch back to the old version. Using Istio, this strategy can be refined by gradually shifting users over to the new version, for example, starting with 20% of the users and then slowly increasing the percentage. At all times, it is very easy to route all users back to the old version if a fatal error is revealed in the new version.