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https://issues.apache.org/jira/browse/HDDS-15791?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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ASF GitHub Bot updated HDDS-15791:
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    Labels: pull-request-available  (was: )

> EC reconstructed RECOVERING container while still idle can be deleted by SCM 
> and recreated as new partial OPEN container
> ------------------------------------------------------------------------------------------------------------------------
>
>                 Key: HDDS-15791
>                 URL: https://issues.apache.org/jira/browse/HDDS-15791
>             Project: Apache Ozone
>          Issue Type: Bug
>            Reporter: Aswin Shakil
>            Assignee: Aswin Shakil
>            Priority: Major
>              Labels: pull-request-available
>
> This issue has been identified by [~deveshsingh] and [~umamahesh] 
> During EC offline reconstruction, the coordinator creates a *RECOVERING* 
> replica on a spare DataNode and writes blocks over time. If reconstruction 
> stalls (e.g. slow block-group processing) longer than 
> `ozone.recovering.container.timeout` (~20m, measured from creation, not last 
> write), the DN scrubber marks the replica *UNHEALTHY* and SCM force-deletes 
> it.
> The coordinator may still be running. The next `WriteChunk` or `PutBlock` 
> finds no container; `HddsDispatcher` auto-creates a new OPEN container 
> instead of failing. The coordinator continues and closes that replica shortly 
> after, leaving a partial container (fewer blocks/chunks than the reference) 
> that SCM can accept as *CLOSED* — silent data loss.
> *Logic flow*
> {code:java}
> Coordinator Phase 1
>   createRecoveringContainer  →  RECOVERING on spare DN
>   (slow / sleep — no writes for extended period)
> StaleRecoveringContainerScrubbingService
>   creationTime + timeout exceeded  →  mark UNHEALTHY
> SCM / Replication Manager
>   force-delete UNHEALTHY replica  →  DELETED on spare DN
> Coordinator resumes writes
>   container == null
>   HddsDispatcher auto-create      →  OPEN (not RECOVERING)
> Coordinator completes
>   closeContainer                  →  CLOSING / CLOSED
> Result: CLOSED replica with partial blocks/chunks at EC index → data loss
> {code}
>  



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