This section outlines new features and enhancements introduced in the Cluster release 5.12.0.

Ceph maintenance label

Implemented the maintenance label to set for Ceph during a managed cluster update. This prevents Ceph rebalance leading to data loss during a managed cluster update.

RGW check box in Container Cloud web UI

Implemented the Enable Object Storage checkbox in the Container Cloud web UI to allow enabling a single-instance RGW Object Storage when creating a Ceph cluster as described in Add a Ceph cluster.


Enhanced Ceph to support RADOS Gateway (RGW) high availability. Now, you can run multiple instances of Ceph RGW in active/active mode.

Cerebro support for StackLight

Enhanced StackLight by adding support for Cerebro, a web UI that visualizes health of Elasticsearch clusters and allows for convenient debugging. Cerebro is disabled by default.

StackLight proxy

Added proxy support for Alertmanager, Metric collector, Salesforce notifier and reporter, and Telemeter client. Now, these StackLight components automatically use the same proxy that is configured for Container Cloud clusters.


Proxy handles only the HTTP and HTTPS traffic. Therefore, for clusters with limited or no Internet access, it is not possible to set up Alertmanager email notifications, which use SMTP, when proxy is used.


Due to a limitation, StackLight fails to integrate with an external proxy with authentication handled by a proxy server. In such cases, the proxy server ignores the HTTP Authorization header for basic authentication passed by Prometheus Alertmanager. Therefore, use proxies without authentication or with authentication handled by a reverse proxy.