StorageReplica - dismount volume and lost data

It seems you are experiencing issues with Storage Replica after the 2025-09 update, leading to the dismounting of the D: drive and potential data loss. Here are some steps and considerations based on common issues and resolutions related to Storage Replica:

1. Check for Known Bugs: The issues you are facing may be related to known bugs in the Storage Replica or S2D code. It is advisable to update to the latest cumulative and out-of-band updates, as these may include fixes for the problems you are encountering.
2. Clear Metadata: If the replica goes to a FAIL state and the D: drive dismounts, you might want to clear any orphaned Storage Replica partition database slots. You can use the Clear-SRMetadata cmdlet to remove orphaned logs and partitions, which may help in restoring the drive to a writable state.
   • For example, you can run:

          Clear-SRMetadata -AllPartitions
     

   • Ensure to restart the server if prompted after clearing the metadata.
3. Monitor System Resources: The event log message you provided indicates an invalid parameter issue. This could be due to insufficient system resources. Ensure that your servers have adequate RAM and resources to handle the workloads alongside Storage Replica operations.
4. Review Configuration: Make sure that your replication topology complies with the supported configurations. Storage Replica supports only one-to-one replication, and any misconfigurations could lead to failures.
5. Consult Microsoft Documentation: For detailed troubleshooting steps and further guidance, refer to Microsoft’s documentation on troubleshooting Storage Replica issues.

If the problem persists, consider reaching out to Microsoft support for assistance, especially since it involves potential data loss.

References:

• Troubleshoot Windows Server storage replica
• Known issues in Storage Replica

ReplicationGroupName: rg
ReplicationGroupId: {8dbe1e9e-838f-40c3-9ec3-9a47559e1a8f}
ReplicaName: D:\
LogPath: \??\L:\System Volume Information\StorageReplicaLogs\{8dbe1e9e-838f-40c3-9ec3-9a47559e1a8f}
Status: An invalid parameter was passed to a service or function.
Start replication for replica.