nats-io/nats-server · error

Error writing term and vote file for %q: %v

Error message

Error writing term and vote file for %q: %v

What it means

writeTermVote failed to durably persist the term_vote file recording the current term and granted vote. Raft requires votes to be durable before use, so the caller (vote granting or campaigning) aborts; the cached n.wtv is cleared to force a retry on the next attempt.

Source

Thrown at server/raft.go:5540

	}

	var buf [termVoteLen]byte
	var le = binary.LittleEndian
	le.PutUint64(buf[0:], n.term)
	copy(buf[8:], n.vote)
	b := buf[:8+len(n.vote)]

	// If the term and vote hasn't changed then don't rewrite to disk.
	if bytes.Equal(n.wtv, b) {
		return nil
	}
	// Stamp latest and write the term & vote file.
	n.wtv = b
	if err := writeTermVote(n.dios, n.sd, n.wtv); err != nil && !n.isClosed() {
		// Clear wtv since we failed.
		n.wtv = nil
		n.setWriteErrLocked(err)
		n.warn("Error writing term and vote file for %q: %v", n.group, err)
		return err
	}
	return nil
}

// voteResponse is a response to a vote request.
type voteResponse struct {
	term    uint64
	peer    string
	granted bool
	empty   bool // "Empty vote", whether this peer's log is empty.
}

const voteResponseLen = 8 + 8 + 1

func (vr *voteResponse) encode() []byte {
	var buf [voteResponseLen]byte
	var le = binary.LittleEndian

View on GitHub (pinned to 3a66a489d2)

Solutions

1. Check disk space and write permissions on the RAFT store dir
2. The vote/campaign is retried on the next election round after the write succeeds
3. Persistent failures indicate failing storage; replace or repair the disk

When it happens

Trigger: Thrown at server/raft.go:5540 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of nats-io/nats-server@3a66a489d2 (2026-09-02). Data as JSON: /api/errors/4286dad813292f8c. Report an issue: GitHub.