Restarting and recreating instances in a group one by one
Instances in a group can be automatically restarted or recreated one by one based on the parameters specified in the instance group deployment policy. These actions can apply both to all instances in the group and to specified instances only.
For example, if the deployment policy specifies a maximum of 1 unavailable instance per group, then only one instance will be down at any given time when sequentially restarting or recreating instances. In this case, each subsequent instance will only be restarted or recreated after the previous one goes into the Running status.
Restarting group instances one by one may be useful, for example, when updating the VM software. This feature allows performing automatic software updates with no downtime of the instance group resources for end users.
Recreating group instances one by one may be useful, for example, when migrating an instance group to a different availability zone. This feature allows recreating instances in a group automatically with no downtime of the instance group resources for end users.
Warning
With the instance stopping strategy, Instance Groups will restart or recreate a VM instance if at least one of the following conditions is met:
- The user stops the instance in Compute Cloud.
- The application or user stops the instance internally.
- The instance fails the application health check.
To restart or recreate instances in a group one by one, use the Yandex Cloud CLI or make an API request.