Mirantis Container Cloud (MCC) becomes part of Mirantis OpenStack for Kubernetes (MOSK)!

Starting with MOSK 25.2, the MOSK documentation set will cover all product layers, including MOSK management (formerly MCC). This means everything you need will be in one place. The separate MCC documentation site will be retired, so please update your bookmarks for continued easy access to the latest content.

PostgreSQL and Patroni¶

This section lists the alerts for the PoststgreSQL and Patroni services.

PostgresqlDataPageCorruption
PostgresqlDeadlocksDetected
PostgresqlInsufficientWorkingMemory
PostgresqlPatroniClusterSplitBrain
PostgresqlPatroniClusterUnlocked
PostgresqlReplicaDown
PostgresqlReplicationNonStreamingReplicas
PostgresqlReplicationPaused
PostgresqlReplicationSlowWalApplication
PostgresqlReplicationSlowWalDownload
PostgresqlReplicationWalArchiveWriteFailing
PostgresqlTargetsOutage
PostgresqlTargetDown

PostgresqlDataPageCorruption¶

Severity	Critical
Summary	Patroni cluster member is experiencing data page corruption.
Description	The `{{ $labels.namespace }}`/`{{ $labels.pod }}` Patroni Pod in the `{{ $labels.cluster }}` cluster fails to calculate the data page checksum due to a possible hardware fault.

PostgresqlDeadlocksDetected¶

Severity	Warning
Summary	PostgreSQL transactions deadlocks.
Description	The transactions submitted to the `{{ $labels.datname }}` database in the `{{ $labels.cluster }}` Patroni cluster in the `{{ $labels.namespace }}` namespace are experiencing deadlocks.

PostgresqlInsufficientWorkingMemory¶

Severity	Warning
Summary	Insufficient memory for PostgreSQL queries.
Description	The query data does not fit into working memory of the `{{ $labels.pod }}` Pod in the `{{ $labels.cluster }}` Patroni cluster in the `{{ $labels.namespace }}` namespace.

PostgresqlPatroniClusterSplitBrain¶

Severity	Critical
Summary	Patroni cluster split-brain detected.
Description	The `{{ $labels.cluster }}` Patroni cluster in the `{{ $labels.namespace }}` namespace has multiple primaries, split-brain detected.

PostgresqlPatroniClusterUnlocked¶

Severity	Major
Summary	Patroni cluster primary node is missing.
Description	The `{{ $labels.cluster }}` Patroni cluster in the `{{ $labels.namespace }}` namespace is down due to missing primary node.

PostgresqlReplicaDown¶

Severity	Warning
Summary	Patroni cluster has replicas with inoperable PostgreSQL.
Description	The `{{ $labels.cluster }}` Patroni cluster in the `{{ $labels.namespace }}` namespace has `{{ $value }}%` of replicas with inoperable PostgreSQL.

PostgresqlReplicationNonStreamingReplicas¶

Severity	Warning
Summary	Patroni cluster has non-streaming replicas.
Description	The `{{ $labels.cluster }}` Patroni cluster in the `{{ $labels.namespace }}` namespace has replicas not streaming segments from the primary node.

PostgresqlReplicationPaused¶

Severity	Major
Summary	Replication has stopped.
Description	Replication has stopped on the `{{ $labels.namespace }}`/`{{ $labels.pod }}` replica Pod in the `{{ $labels.cluster }}` cluster.

PostgresqlReplicationSlowWalApplication¶

Severity	Warning
Summary	WAL segment application is slow.
Description	Slow replication while applying WAL segments on the `{{ $labels.namespace }}`/`{{ $labels.pod }}` replica Pod in the `{{ $labels.cluster }}` cluster.

PostgresqlReplicationSlowWalDownload¶

Severity	Warning
Summary	Streaming replication is slow.
Description	Slow replication while downloading WAL segments for the `{{ $labels.namespace }}`/`{{ $labels.pod }}` replica Pod in the `{{ $labels.cluster }}` cluster.

PostgresqlReplicationWalArchiveWriteFailing¶

Severity	Major
Summary	Patroni cluster WAL segment writes are failing.
Description	The `{{ $labels.namespace }}`/`{{ $labels.pod }}` Patroni Pod in the `{{ $labels.cluster }}` cluster fails to write replication segments.

PostgresqlTargetsOutage¶

Replaced with PostgresqlTargetDown in MCC 2.25.0 (17.0.0 and 16.0.0)

Severity	Critical
Summary	Patroni cluster Prometheus targets outage.
Description	Prometheus fails to scrape metrics from 2/3 of Patroni `{{ $labels.cluster }}` cluster endpoints (more than 1/10 failed scrapes).

PostgresqlTargetDown¶

Since MCC 2.25.0 (17.0.0 and 16.0.0) to replace PostgresqlTargetsOutage

Severity	Critical
Summary	Patroni cluster Prometheus target down.
Description	Prometheus fails to scrape metrics from the `{{ $labels.pod }}` Pod of the `{{ $labels.cluster }}` cluster on the `{{ $labels.node }}` node.