XTLS/Xray-core · error

failed to write request header

Error message

failed to write request header

What it means

Error "failed to write request header" thrown in XTLS/Xray-core.

Source

Thrown at proxy/trojan/protocol.go:42

	maxLength = 8192

	commandTCP byte = 1
	commandUDP byte = 3
)

// ConnWriter is TCP Connection Writer Wrapper for trojan protocol
type ConnWriter struct {
	io.Writer
	Target     net.Destination
	Account    *MemoryAccount
	headerSent bool
}

// Write implements io.Writer
func (c *ConnWriter) Write(p []byte) (n int, err error) {
	if !c.headerSent {
		if err := c.writeHeader(); err != nil {
			return 0, errors.New("failed to write request header").Base(err)
		}
	}

	return c.Writer.Write(p)
}

// WriteMultiBuffer implements buf.Writer
func (c *ConnWriter) WriteMultiBuffer(mb buf.MultiBuffer) error {
	defer buf.ReleaseMulti(mb)

	for _, b := range mb {
		if !b.IsEmpty() {
			if _, err := c.Write(b.Bytes()); err != nil {
				return err
			}
		}
	}

View on GitHub (pinned to 7d214f8b09)

When it happens

Trigger: Thrown at proxy/trojan/protocol.go:42 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of XTLS/Xray-core@7d214f8b09 (2026-08-15). Data as JSON: /api/errors/00975e811eb907ac. Report an issue: GitHub.