juicedata/juicefs · error

unsupported driver %s

Error message

unsupported driver %s

What it means

newTkvClient looked up the driver name in the package-level drivers registry and found no matching constructor. This is a configuration validation error: the engine string (e.g., tikv, etcd, badger, fdb) is misspelled, unregistered, or the build was compiled without that backend's tags.

Source

Thrown at pkg/meta/tkv.go:110

		return true
	})
}

type kvMeta struct {
	*baseMeta
	client tkvClient
	snap   map[Ino]*DumpedEntry
}

var _ Meta = (*kvMeta)(nil)
var _ engine = (*kvMeta)(nil)

var drivers = make(map[string]func(string) (tkvClient, error))

func newTkvClient(driver, addr string) (tkvClient, error) {
	fn, ok := drivers[driver]
	if !ok {
		return nil, fmt.Errorf("unsupported driver %s", driver)
	}
	return fn(addr)
}

func newKVMeta(driver, addr string, conf *Config) (Meta, error) {
	client, err := newTkvClient(driver, addr)
	if err != nil {
		return nil, fmt.Errorf("connect to addr %s: %s", addr, err)
	}
	// TODO: ping server and check latency > Millisecond
	// logger.Warnf("The latency to database is too high: %s", time.Since(start))
	m := &kvMeta{
		baseMeta: newBaseMeta(addr, conf),
		client:   client,
	}
	m.en = m
	return m, nil
}

View on GitHub (pinned to c9a67b23e8)

Solutions

1. Check the driver name spelling in the metadata URL
2. Use a build that includes the engine (e.g. make juicefs.fdb for FoundationDB)

When it happens

Trigger: Thrown at pkg/meta/tkv.go:110 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of juicedata/juicefs@c9a67b23e8 (2026-09-06). Data as JSON: /api/errors/e9cfb18b24bca7e7. Report an issue: GitHub.