When draining Istio pods some nodes may not drain because they have a replica count of 1, while 3 or
more replicas are required. In order to avoid this, you should set the minimum replica count for each
property to at least 3.
When backing up and draining Istio nodes you may see errors like:
kubectl drain` failed to evict and reschedule pods to another node due to PodDisruptionBudget definitions:
===
NAMESPACE NAME MIN AVAILABLE MAX UNAVAILABLE ALLOWED DISRUPTIONS AGE
istio-system istio-ingressgateway 1 N/A 2 5d11h
istio-system istio-pilot 1 N/A 2 5d11h
===
For istio-ingressgateway and istio-pilot you can set the
istio.ingressgateway.replicaCountMin and istio.pilot.replicaCountMin
properties to 3 or higher. See the
Configuration properties reference,
istio.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-12 UTC."],[[["Version 1.6 of the Apigee hybrid documentation is end of life, and users should upgrade to a newer version."],["To prevent draining issues with Istio pods, set the minimum replica count for properties such as `istio.ingressgateway.replicaCountMin` and `istio.pilot.replicaCountMin` to at least 3."],["When backing up and draining Istio nodes, errors may occur due to PodDisruptionBudget definitions, particularly with `istio-ingressgateway` and `istio-pilot`."],["For other Istio components without a `replicaCountMin` property, refer to the GKE documentation for manually upgrading a cluster or node pool or Istio documentation for `IstioOperator` options."]]],[]]
