# S01012 {#s01012}

## Error Code {#error_code .section}

S01012

## Error Message {#error_message .section}

`No available replica for the chunk <chunkId> is found on the controller. RefId:S01012`

## Probable Causes {#probable_causes .section}

A transaction checks the number of available replicas after acquiring distributed locks for the involved chunks. This error is reported if the number is 0, and the transaction is rolled back.

Specific reasons include:

-   All nodes hosting the chunk replicas are offline.
-   The online replicas of the chunk have versions inconsistent with the controller.

## Solutions {#solutions .section}

Execute `getClusterChunksStatus` on the controller to view the status of each chunk replica for further troubleshooting.

**Parent topic:**[Error Code Reference](../../Troubleshooting/ErrorCode.md)

