[test scenario] window PoSt - a corrupted sector on disk is declared as faulty

[raulk]

Describe the test scenario.

Verify that Lotus successfully declares a corrupted sector as faulty during its appropriate proving window. By doing so, it incurs in the Fault Fee (per diem), but avoids the Sector Penalty (which is levied if the prover neither proves nor declares a fault).

Provide any background and technical implementation details.

1. Perform a bunch of deals in the network.
2. On the miner, wait until the sectors are sealed.
3. Pick the first sector, somehow locate the data on disk, and flip a byte at offset N (configurable by parameter).
4. Wait until the proving window elapses.
5. Query the miner actor to verify that the sector is declared as faulty, not because the network found it to be so, but because the miner informed of such situation (is this identifiable?).
6. Ensure that the miner has been deducted the Fault Fee only, but not the Sector Penalty.
7. Restore the mangled byte on disk by flipping it again.
8. Wait until the next proving window, and verify that the sector is healthy again.
9. Verify that the Fault Fee was not deducted for that day.
10. Wait for another proving window.
11. Verify that no fees are deducted.

What should we measure?

• Deducted fees / penalties.
• Sector statuses.

Discomfort factor (0-10).

TBD.

Additional remarks.

[raulk]

Relevant code in Lotus that declares a fault to the network: https://github.com/filecoin-project/lotus/blob/0b1fa54a4dd23b395ece8125591c6a87f3d132e5/storage/wdpost_run.go#L192