Failed Partitions

A failed partition is an event source ID where an observer encountered an unhandled exception while processing an event. When a partition fails, Chronicle pauses that partition’s processing and records the failure details — the failing sequence number, the exception message, and the number of attempts. All other partitions continue processing normally.

Fixing a failed partition typically involves correcting the application bug that caused the exception and then using observers retry-partition to resume processing.

list

Lists all failed partitions across all observers, or for a specific observer.

cratis chronicle failed-partitions list

Options

Flag	Description
`-e, --event-store <NAME>`	Event store to inspect. Defaults to `default`.
`-n, --namespace <NAME>`	Namespace to inspect. Defaults to `Default`.
`--observer <OBSERVER_ID>`	Filter to a specific observer.

Examples

List all failed partitions:

cratis chronicle failed-partitions list

List failed partitions for a specific observer:

cratis chronicle failed-partitions list --observer my-observer-id

Plain output for scripting:

cratis chronicle failed-partitions list --output plain

show

Shows details about a specific failed partition, including the error message, the failing sequence number, and the attempt history.

cratis chronicle failed-partitions show <OBSERVER_ID> <PARTITION>

Arguments

Argument	Description
`OBSERVER_ID`	The observer that owns the failed partition.
`PARTITION`	The event source ID of the failed partition.

Options

Flag	Description
`-e, --event-store <NAME>`	Event store to inspect. Defaults to `default`.
`-n, --namespace <NAME>`	Namespace to inspect. Defaults to `Default`.
`--detailed`	Show full stack traces and all recorded attempts. Defaults to `false`.

By default, the command shows a truncated error message. Use --detailed to see the full stack trace and the history of all previous attempts. Use --output json to get the complete error information in a machine-readable form.

Examples

Show the failed partition summary:

cratis chronicle failed-partitions show my-observer-id user-42

Show full stack traces and all attempt history:

cratis chronicle failed-partitions show my-observer-id user-42 --detailed

Get the full error as JSON:

cratis chronicle failed-partitions show my-observer-id user-42 -o json

Next Steps

After reviewing a failed partition:

Fix the application bug that caused the failure.
Use observers retry-partition to resume the partition without replaying from scratch:
Terminal window
```
cratis chronicle observers retry-partition my-observer-id user-42
```
If the partition state is corrupt and must be rebuilt, use observers replay-partition:
Terminal window
```
cratis chronicle observers replay-partition my-observer-id user-42
```