Operator conditions

Operator conditions

This guide outlines how Operator Lifecycle Manager (OLM) uses Operator conditions.

About Operator conditions

As part of its role in managing the lifecycle of an Operator, Operator Lifecycle Manager (OLM) infers the state of an Operator from the state of Kubernetes resources that define the Operator. While this approach provides some level of assurance that an Operator is in a given state, there are many instances where an Operator might need to communicate information to OLM that could not be inferred otherwise. This information can then be used by OLM to better manage the lifecycle of the Operator.

OLM provides a custom resource definition (CRD) called OperatorCondition that allows Operators to communicate conditions to OLM. There are a set of supported conditions that influence management of the Operator by OLM when present in the Spec.Conditions array of an OperatorCondition resource.

By default, the Spec.Conditions array is not present in an OperatorCondition object until it is either added by a user or as a result of custom Operator logic.

Supported conditions

Operator Lifecycle Manager (OLM) supports the following Operator conditions.

Upgradeable condition

The Upgradeable Operator condition prevents an existing cluster service version (CSV) from being replaced by a newer version of the CSV. This condition is useful when:

An Operator is about to start a critical process and should not be upgraded until the process is completed.
An Operator is performing a migration of custom resources (CRs) that must be completed before the Operator is ready to be upgraded.

Setting the Upgradeable Operator condition to the False value does not avoid pod disruption. If you must ensure your pods are not disrupted, see “Using pod disruption budgets to specify the number of pods that must be up” and “Graceful termination” in the “Additional resources” section.

Example Upgradeable Operator condition

apiVersion: operators.coreos.com/v1
kind: OperatorCondition
metadata:
  name: my-operator
  namespace: operators
spec:
  conditions:
  - type: Upgradeable (1)
    status: "False" (2)
    reason: "migration"
    message: "The Operator is performing a migration."
    lastTransitionTime: "2020-08-24T23:15:55Z"

1	Name of the condition.
2	A `False` value indicates the Operator is not ready to be upgraded. OLM prevents a CSV that replaces the existing CSV of the Operator from leaving the `Pending` phase. A `False` value does not block cluster upgrades.