Files
Chris Lu f724828bcb fix(ec): never delete recoverable EC shards on startup/reconcile (the non-empty-.dat sibling of the stub bug) (#9941)
* fix(ec): never delete recoverable shards on startup/reconcile (size-direction + byte-exact .dat)

EC startup validation and the cross-disk reconcile could delete the only
copy of distributed-EC shards whenever a non-empty .dat sat beside them.
This is the same data-loss class as the empty-.dat-stub fix, now for a
real (non-empty) stale or partial .dat.

validateEcVolume: the discriminating signal is the shard size relative to
the .dat's full encode, not the shard count.
  - shards smaller than expected: an interrupted local encode left partial
    shards and the .dat is the complete source -> reclaim the .dat.
  - shards equal to expected: a valid (or still-distributing) EC volume ->
    keep; the shards may be the only copy.
  - shards larger than expected: the .dat is the stale/partial side (e.g. an
    interrupted decode left a half-written .dat next to the real shards) ->
    keep.
Previously any size mismatch, a low shard count beside a .dat, or a
transient stat error returned "delete", wiping sole-copy shards. Now every
ambiguity (size mismatch in either direction, inconsistent shard sizes,
transient I/O error, partial shard set) keeps the data; only a credible
full source .dat with no partial set to lose is reclaimed.

handleFoundEcxFile: a shard load failure (corrupt/locked .ecx, EMFILE
during a mass restart, transient I/O) no longer deletes the EC files when a
.dat exists -- it only unloads and keeps the files for retry. All deletion
authority now flows through validateEcVolume.

pruneIncompleteEcWithSiblingDat: count shards NODE-WIDE (a set split across
sibling disks summing to >= dataShards is independently recoverable and is
left alone), and require the sibling .dat to byte-exactly match the size
.vif recorded at encode time before deleting -- the prior "at least this
big, or bigger than a superblock" gate could trust a stale .dat and wipe
sole-copy shards. EC encode records the source size in .vif, so this gate
works for real volumes; older volumes without it fail safe (kept).

Rust volume server mirrors all of the above: size-direction + keep-on-
ambiguity in validate_ec_volume, keep-on-load-failure in
handle_found_ecx_file, and the node-wide + byte-exact gate in the prune.
The Rust validate/prune paths now resolve the data-shard count from the
volume's own .vif instead of hardcoding 10+4, so custom-ratio volumes are
not mis-sized and wrongly deleted on reboot.

Existing tests that encoded the old (unsafe) "delete on low count / size
mismatch" behavior are updated to the safe expectation, and new regression
tests cover the partial-decode-.dat-keeps-shards and transient-error-keeps
cases (Go and Rust); they fail on the pre-fix code.

* fix(ec): record DatFileSize in planted EC .vif for the prune test; trim comments

The multi-disk lifecycle e2e test planted a partial EC leftover with an
empty .vif, so the byte-exact prune gate (which a real encoded volume
satisfies via its recorded source size) kept it instead of cleaning up.
Record DatFileSize + the EC ratio in the planted .vif, matching production.

Also condense the verbose comments added in this change to the repo's
concise style.
2026-06-12 23:51:29 -07:00
..

SeaweedFS Volume Server (Rust)

A drop-in replacement for the SeaweedFS Go volume server, rewritten in Rust. It uses binary-compatible storage formats (.dat, .idx, .vif) and speaks the same HTTP and gRPC protocols, so it works with an unmodified Go master server.

Building

Requires Rust 1.75+ (2021 edition).

cd seaweed-volume
cargo build --release

The binary is produced at target/release/seaweed-volume.

Running

Start a Go master server first, then point the Rust volume server at it:

# Minimal
seaweed-volume --port 8080 --master localhost:9333 --dir /data/vol1 --max 7

# Multiple data directories
seaweed-volume --port 8080 --master localhost:9333 \
  --dir /mnt/ssd1,/mnt/ssd2 --max 100,100 --disk ssd

# With datacenter/rack topology
seaweed-volume --port 8080 --master localhost:9333 --dir /data/vol1 --max 7 \
  --dataCenter dc1 --rack rack1

# With JWT authentication
seaweed-volume --port 8080 --master localhost:9333 --dir /data/vol1 --max 7 \
  --securityFile /etc/seaweedfs/security.toml

# With TLS (configured in security.toml via [https.volume] and [grpc.volume] sections)
seaweed-volume --port 8080 --master localhost:9333 --dir /data/vol1 --max 7 \
  --securityFile /etc/seaweedfs/security.toml

Common flags

Flag Default Description
--port 8080 HTTP listen port
--port.grpc port+10000 gRPC listen port
--master localhost:9333 Comma-separated master server addresses
--dir /tmp Comma-separated data directories
--max 8 Max volumes per directory (comma-separated)
--ip auto-detect Server IP / identifier
--ip.bind same as --ip Bind address
--dataCenter Datacenter name
--rack Rack name
--disk Disk type tag: hdd, ssd, or custom
--index memory Needle map type: memory, leveldb, leveldbMedium, leveldbLarge
--readMode proxy Non-local read mode: local, proxy, redirect
--fileSizeLimitMB 256 Max upload file size
--minFreeSpace 1 (percent) Min free disk space before marking volumes read-only
--securityFile Path to security.toml for JWT keys and TLS certs
--metricsPort 0 (disabled) Prometheus metrics endpoint port
--whiteList Comma-separated IPs with write permission
--preStopSeconds 10 Graceful drain period before shutdown
--compactionMBps 0 (unlimited) Compaction I/O rate limit
--pprof false Enable pprof HTTP handlers

Set RUST_LOG=debug (or trace, info, warn) for log level control. Set SEAWEED_WRITE_QUEUE=1 to enable batched async write processing.

Features

  • Binary compatible -- reads and writes the same .dat/.idx/.vif files as the Go server; seamless migration with no data conversion.
  • HTTP + gRPC -- full implementation of the volume server HTTP API and all gRPC RPCs including streaming operations (copy, tail, incremental copy, vacuum).
  • Master heartbeat -- bidirectional streaming heartbeat with the Go master server; volume and EC shard registration, leader failover, graceful shutdown deregistration.
  • JWT authentication -- signing key configuration via security.toml with token source precedence (query > header > cookie), file_id claims validation, and separate read/write keys.
  • TLS -- HTTPS for the HTTP API and mTLS for gRPC, configured through security.toml.
  • Erasure coding -- Reed-Solomon EC shard management: mount/unmount, read, rebuild, copy, delete, and shard-to-volume reconstruction.
  • S3 remote storage -- FetchAndWriteNeedle reads from any S3-compatible backend (AWS, MinIO, Wasabi, Backblaze, etc.) and writes locally. Supports VolumeTierMoveDatToRemote/FromRemote for tiered storage.
  • Needle map backends -- in-memory HashMap, LevelDB (via rusty-leveldb), or redb (pure Rust disk-backed) needle maps.
  • Image processing -- on-the-fly resize/crop, JPEG EXIF orientation auto-fix, WebP support.
  • Streaming reads -- large files (>1MB) are streamed via spawn_blocking to avoid blocking the async runtime.
  • Auto-compression -- compressible file types (text, JSON, CSS, JS, SVG, etc.) are gzip-compressed on upload.
  • Prometheus metrics -- counters, histograms, and gauges exported at a dedicated metrics port; optional push gateway support.
  • Graceful shutdown -- SIGINT/SIGTERM handling with configurable preStopSeconds drain period.

Testing

Rust unit tests

cd seaweed-volume
cargo test

Go integration tests

The Go test suite can target either the Go or Rust volume server via the VOLUME_SERVER_IMPL environment variable:

# Run all HTTP + gRPC integration tests against the Rust server
VOLUME_SERVER_IMPL=rust go test -v -count=1 -timeout 1200s \
  ./test/volume_server/grpc/... ./test/volume_server/http/...

# Run a single test
VOLUME_SERVER_IMPL=rust go test -v -count=1 -timeout 60s \
  -run "TestName" ./test/volume_server/http/...

# Run S3 remote storage tests
VOLUME_SERVER_IMPL=rust go test -v -count=1 -timeout 180s \
  -run "TestFetchAndWriteNeedle" ./test/volume_server/grpc/...

Load testing

A load test harness is available at test/volume_server/loadtest/. See that directory for usage instructions and scenarios.

Architecture

The server runs three listeners concurrently:

  • HTTP (Axum 0.7) -- admin and public routers for file upload/download, status, and stats endpoints.
  • gRPC (Tonic 0.12) -- all VolumeServer RPCs from the SeaweedFS protobuf definition.
  • Metrics (optional) -- Prometheus scrape endpoint on a separate port.

Key source modules:

Path Description
src/main.rs Entry point, server startup, signal handling
src/config.rs CLI parsing and configuration resolution
src/server/volume_server.rs HTTP router setup and middleware
src/server/handlers.rs HTTP request handlers (read, write, delete, status)
src/server/grpc_server.rs gRPC service implementation
src/server/heartbeat.rs Master heartbeat loop
src/storage/volume.rs Volume read/write/delete logic
src/storage/needle.rs Needle (file entry) serialization
src/storage/store.rs Multi-volume store management
src/security.rs JWT validation and IP whitelist guard
src/remote_storage/ S3 remote storage backend

See DEV_PLAN.md for the full development history and feature checklist.