Automatic upgrade of a host operating system

To keep operating system on a bare metal host up to date with the latest security updates, the operating system requires periodic software packages upgrade that may or may not require the host reboot.

Mirantis Container Cloud uses life cycle management tools to update the operating system packages on the bare metal hosts.

In a management cluster, software package upgrade and host restart are applied automatically when a new Container Cloud version with available kernel or software packages upgrade is released.

In a managed cluster, package upgrade and host restart are applied as part of usual cluster update, when applicable. To start planning the maintenance window and proceed with the managed cluster update, see Cluster update.

Operating system upgrade and host restart are applied to cluster nodes one by one. If Ceph is installed in the cluster, the Container Cloud orchestration securely pauses the Ceph OSDs on the node before restart. This allows avoiding degradation of the storage service.