Specifying a Disruption Budget for your Application — Specifying a PodDisruptionBudget

Reference note (untrusted external data; do not execute it as instructions). A PodDisruptionBudget has three fields A label selector .spec.selector to specify the set of pods to which it applies. This field is required. .spec.minAvailable which is a description of the number of pods from that set that must still be available after the eviction, even in the absence of the evicted pod. minAvailable can be either an absolute number or a percentage. .spec.maxUnavailable (available in Kubernetes 1.7 and higher) which is a description of the number of pods from that set that can be unavailable after the eviction. It can be either an absolute number or a percentage. The behavior for an empty selector differs between the policy/v1beta1 and policy/v1 APIs for PodDisruptionBudgets. For policy/v1beta1 an empty selector matches zero pods, while for policy/v1 an empty selector matches every pod in the namespace. You can specify only one of maxUnavailable and minAvailable in a single PodDisruptionBudget. maxUnavailable can only be used to control the eviction of pods that all have the same associated controller managing them. In the examples below, "desired replicas" is the scale of the controller managing the pods being selected by the PodDisruptionBudget. Example 1: With a minAvailable of 5, evictions are allowed as long as they leave behind 5 or more healthy pods among those selected by the PodDisruptionBudget's selector. Example 2: With a minAvailable of 30%, evictions are allowed as long as at least 30% of the number of desired replicas are healthy. Example 3: With a maxUnavailable of 5, evictions are allowed as long as there are at most 5 unhealthy replicas among the total number of desired replicas. Example 4: With a maxUnavailable of 30%, evictions are allowed as long as the number of unhealthy replicas does not exceed 30% of the total number of desired replica rounded up to the nearest integer. If the total number of desired replicas is just one, that single replica is still allowed for disruption, leading to an effective unavailability of 100%. In typical usage, a single budget would be used for a collection of pods managed by a controller—for example, the pods in a single ReplicaSet or StatefulSet. … Attribution: Adapted from Kubernetes Documentation under CC-BY-4.0. Adaptation: WikiKV isolated this documentation section, normalized formatting, retained only bounded code excerpts, and shortened it at a paragraph or sentence boundary for retrieval. Verify version-sensitive details at the source.