New features:
- PodDisruption budget is configured automatically in order to prevent multiple pods being shut down by k8s
- topologyKey is now configurable. It addresses #772
- spec.restart: "RollingRestart" attribute has been added in order to initiate graceful restart of a cluster. Use it with a patch command.
- Added a support for Kubernetes secrets in settings section, e.g. for ClickHouse user/password.
Changed:
- Pod maintenance logic during all operations that require pod restart has been improved:
- Wait condition is enabled for a pod to be removed from ClickHouse cluster.
- Wait condition is added for running queries to complete (up to 5 minutes).
- terminationGracePeriod has been increased to 60 seconds.
- Timeout for DDL operations has been increased to 60 seconds. That addresses issues with schema management on slow clusters.
- Base image is switched to RedHat UBI
- ZooKeeper image version has been rolled back to 3.6.1 since we have some problems with 3.6.3
- CRD apiVersion has been upgraded from apiextensions.k8s.io/v1beta1 to apiextensions.k8s.io/v1. The v1beta1 manifests are still available under descriptive names.
Fixed:
- Fixed a bug with non-working custom ports
- Fixed a bug with replicas being incorrectly deleted from ZooKeeper for retained volumes
Note: Upgrade from the previous version will result in restart of ClickHouse clusters.