matanper opened a new issue, #69864:
URL: https://github.com/apache/doris/issues/69864

   ### Search before asking
   
   - [x] I had searched in the 
[issues](https://github.com/apache/doris/issues?q=is%3Aissue) and found no 
similar issues.
   
   ### Version
   
   4.1.4 (cloud mode, peer file cache reads). master is the same: 
`be/src/cloud/cloud_internal_service.cpp:778-781`:
   
   ```cpp
   Status read_status = read_file_block(fb, file_size, out, 
response_attachment);
   if (!read_status.ok()) {
       set_error_response(response, "read cache file error");   // 
INTERNAL_ERROR
       return read_status;
   }
   ```
   
   ### Description
   
   When a peer serves a block that its cache says is `DOWNLOADED` but whose 
cache file is gone (deleted underneath the cache, a race with removal, a disk 
problem), `read_file_block` returns `NOT_FOUND`. The handler:
   
   - answers `INTERNAL_ERROR`, which the requester counts as a peer failure 
(`peer_file_cache_reader.cpp:90`, `consecutive_failures`) and, after 
`cache_peer_read_failure_threshold` of them, stops using an otherwise healthy 
peer;
   - leaves the block in its cache, so every later request for that block fails 
the same way, on every requester.
   
   A local read of such a block already self-heals (it removes the cached entry 
on `NOT_FOUND` and falls back to remote), but the peer-serve path does not.
   
   ### Solution
   
   On `NOT_FOUND` from `read_file_block`, remove the block from the serving 
BE's cache (as a local read does) and answer `NOT_FOUND`, which the requester 
already treats as a soft miss (rotate the candidate and fall back to S3) rather 
than a peer failure.
   
   ### How to Reproduce?
   
   With peer reads enabled, warm a block on BE A, delete its cache file on 
disk, then read the same range from BE B so it asks A: A answers "read cache 
file error" on every attempt, and B eventually marks A unhealthy.
   
   ### Anything Else?
   
   ### Are you willing to submit PR?
   
   - [x] Yes I am willing to submit a PR!
   
   ### Code of Conduct
   
   - [x] I agree to follow this project's [Code of 
Conduct](https://www.apache.org/foundation/policies/conduct)
   


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