vitessio/vitess · error

SHOW BINARY LOGS returned no rows

Error message

SHOW BINARY LOGS returned no rows

What it means

limitOpenBinlogSize in snapshot_conn runs SHOW BINARY LOGS on the source MySQL to compute binlog sizes for a snapshot stream. If the query succeeds but returns no rows, it cannot identify the current binlog and fails with "SHOW BINARY LOGS returned no rows". A MySQL server always reports at least its current binlog when binary logging is enabled, so no rows indicates binlogs are unavailable.

Solutions

1. Enable binary logging on the source MySQL (log_bin=ON) and restart mysqld.
2. Verify with `SHOW BINARY LOGS;` directly on the MySQL instance that rows are returned.
3. Ensure the connecting user has sufficient privileges (REPLICATION CLIENT) to see binlogs.
4. If the source is a managed instance without binlogs, snapshot streaming from it is unsupported — choose a different source.

Example fix

// before (my.cnf)
# log_bin not set -> SHOW BINARY LOGS empty
// after (my.cnf)
log_bin = mysql-bin
server_id = 1

res, err := conn.ExecuteFetch("SHOW BINARY LOGS", -1, false)
if err != nil || res == nil || len(res.Rows) == 0 {
  return errors.New("source MySQL has no binary logs; enable log_bin before snapshot streaming")
}

if err != nil && strings.Contains(err.Error(), "SHOW BINARY LOGS returned no rows") {
  return fmt.Errorf("source %s must have binary logging enabled: %w", alias, err)
}

When it happens

Trigger: VStreamWithSnapshot against a MySQL server with binary logging disabled (log_bin=OFF), or a server where SHOW BINARY LOGS is inaccessible/empty (e.g. managed setups hiding binlogs, or wrong user privileges combined with no logs).

Common situations: Pointing a VReplication snapshot stream at an rdonly/replica tablet whose MySQL has log_bin disabled; cloud-managed MySQL instances without binary logs; MySQL restarted into a state without binlog files.

Related errors

• bad encoding
• binlog stream client charset
• can't get charset to check binlog stream
• error in connecting to mysql db with connection
• error reading binlog event

AI-assisted analysis of vitessio/vitess@01a25a7d17 (2026-09-01). Data as JSON: /api/errors/1dc176695bc5ecb7. Report an issue: GitHub.

Appendix: source

Thrown at go/vt/vttablet/tabletserver/vstreamer/snapshot_conn.go:164

	_, _ = conn.ExecuteFetch("rollback", 1, false)
	conn.Conn.Close()
}

func mysqlConnect(ctx context.Context, cp dbconfigs.Connector) (*mysql.Conn, error) {
	return cp.Connect(ctx)
}

// limitOpenBinlogSize will rotate the binary log if the current binary
// log is greater than binlogRotationThreshold.
func (conn *snapshotConn) limitOpenBinlogSize() (bool, error) {
	rotatedLog := false
	// Output: https://dev.mysql.com/doc/refman/en/show-binary-logs.html
	res, err := conn.ExecuteFetch("SHOW BINARY LOGS", -1, false)
	if err != nil {
		return rotatedLog, err
	}
	if res == nil || len(res.Rows) == 0 {
		return rotatedLog, errors.New("SHOW BINARY LOGS returned no rows")
	}
	// the current log will be the last one in the results
	curLogIdx := len(res.Rows) - 1
	curLogSize, err := res.Rows[curLogIdx][1].ToInt64()
	if err != nil {
		return rotatedLog, err
	}
	if curLogSize > atomic.LoadInt64(&vttablet.VStreamerBinlogRotationThreshold) {
		if _, err = conn.ExecuteFetch("FLUSH BINARY LOGS", 0, false); err != nil {
			return rotatedLog, err
		}
		rotatedLog = true
	}
	return rotatedLog, nil
}

// GetBinlogRotationThreshold returns the current byte size at which a VStreamer
// will attempt to rotate the binary log before starting a GTID snapshot based

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