* volume: after losing the leader, dial the leader the other masters name When the heartbeat stream to the leader breaks and that master stays unreachable (partitioned or powered off, so dials hang rather than being refused), the volume server could take close to a minute to register with the new leader, and the new leader answered assigns with "no volume server capacity registered yet" in the meantime. Two things in the retry path added up: - refreshLeaderFromPeers asked the seed masters in order with up to 5s each, inside a budget of one pulse (5s by default). With the lost master listed first, the whole budget went to it and the live peers that already knew the new leader were never asked. - Even when the refresh found the new leader, the loop moved on to the next seed master. When the lost leader had been reached through a redirect, the next seed can be that same master, so the loop dialed it again and waited out the 20s gRPC connect timeout. Ask the lost master last, and when the refresh names a leader other than the lost master, dial it next. Assisted-by: Claude <noreply@anthropic.com> * rust volume: dial the leader the other masters name after losing one Mirror the Go heartbeat change: refresh_leader_from_peers asks the lost master last and returns the leader it found, and the loop dials that leader next instead of a seed that can be the unreachable master itself. Generated with [Devin](https://devin.ai) Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com> * rust volume: let a named leader consume the next seed slot Restarting the seed scan on every redirect let an earlier seed that keeps reporting the dead leader starve every seed after it: the loop bounced between the redirect target and the next seed forever. Go consumes the next range value for the redirect instead, so a pass always reaches every seed. Drop the breaks so new_leader overrides the next slot the same way. Generated with [Devin](https://devin.ai) Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com> * volume: try a named leader on top of the seed scan A reported leader used to replace the next seed slot: with seeds A,B and A persistently naming a dead leader X, X consumed B's slot on every pass so B was never dialed. The hint is now a one-shot attempt made before the seed it would have displaced. Its own result stays pending when a seed attempt names nothing, so a live follower's redirect chain is followed while every seed is still dialed on every pass. Mirrors between the Go and Rust volume servers. Generated with [Devin](https://devin.ai) Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com> * volume: follow a fresh leader hint before the pending seed A named leader whose stream breaks can leave the peer refresh naming its replacement; the loop then dialed the pending seed first and paid a dead master's connect timeout ahead of the fresh name. Fresh hints are now followed right away, bounded by the seed count and stopping once a name repeats, so a peer that keeps naming the same dead leader still cannot starve the seed scan. Go and Rust mirrored. * volume: dial each named leader once per pass (Go + Rust) A name that stays pending after the hint chain — the cap was hit, or the refresh named one already dialed — was retried before every later seed in the pass: each seed reset the hint budget, so a dead leader still cost a sleep and a connect timeout per seed. Track the names dialed in a pass, seeds included, and skip a hint that repeats one. Generated with [Devin](https://devin.ai) Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com> * volume: let a seed's named leader replace a pending hint (Go + Rust) The seed dial runs after the hint chain, so the leader it names is the freshest answer the pass has — but it was dropped whenever a stale hint was still pending, and the next seed then chased the older name first. Generated with [Devin](https://devin.ai) Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com> * volume: keep an untried leader hint over the seed's stale answer (Go + Rust) A seed that keeps naming a stale leader spends the per-pass hint budget on it; its own answer then overwrote the live name the hint chain had just reached, so that leader was never dialed. A pending hint now survives the seed dial until it has been tried. --------- Co-authored-by: user.email <chrislusf@users.noreply.github.com> Co-authored-by: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
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 1.91.1+ (2024 edition), matching rust-version in Cargo.toml.
The patch release matters: 1.91.0 does not build. The edition itself only needs
1.85; the higher floor comes from the dependency tree — chiefly the AWS SDK — so
it moves with those crates. CI builds on the latest stable.
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 |
--compactionMaxParallelCommits |
0 (unlimited) |
Max concurrent vacuum commits |
--pprof |
false |
Enable pprof HTTP handlers |
Set RUST_LOG=debug (or trace, info, warn) for log level control.
Durable (fsync=true) uploads always go through per-volume batching workers
that share one .dat/.idx sync per batch, matching the Go volume server;
non-fsync writes take the synchronous path.
Features
- Binary compatible -- reads and writes the same
.dat/.idx/.viffiles 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.tomlwith 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 --
FetchAndWriteNeedlereads from any S3-compatible backend (AWS, MinIO, Wasabi, Backblaze, etc.) and writes locally. SupportsVolumeTierMoveDatToRemote/FromRemotefor 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_blockingto 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
preStopSecondsdrain 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
VolumeServerRPCs 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.