hashicorp/terraform · error

Cannot quote scp command, target platform unknown: %s

Error message

Cannot quote scp command, target platform unknown: %s

What it means

Returned by quoteScpCommand when target_platform is neither TargetPlatformUnix nor TargetPlatformWindows. The function selects shell-quoting rules per platform (POSIX vs Windows ArgvSplit); any other value has no quoting strategy and is rejected before constructing the scp command.

Source

Thrown at internal/communicator/ssh/communicator.go:898

	net.Conn
	Bastion *ssh.Client
}

func (c *bastionConn) Close() error {
	c.Conn.Close()
	return c.Bastion.Close()
}

func quoteScpCommand(args []string, targetPlatform string) (string, error) {
	if targetPlatform == TargetPlatformUnix {
		return shquot.POSIXShell(args), nil
	}
	if targetPlatform == TargetPlatformWindows {
		cmd, args := shquot.WindowsArgvSplit(args)
		return fmt.Sprintf("%s %s", cmd, args), nil
	}

	return "", fmt.Errorf("Cannot quote scp command, target platform unknown: %s", targetPlatform)

}

View on GitHub (pinned to d32a084675)

Solutions

1. Set target_platform to either "unix" or "windows" (or omit it for the unix default).
2. If constructing connectionInfo programmatically, always go through parseConnectionInfo so defaults and validation apply.
3. Treat this error as a bug if it appears with a standard config — it indicates an internal invariant was violated.

Example fix

// before
connection {
  host            = aws_instance.web.public_ip
  target_platform = "linux"
}

// after
connection {
  host            = aws_instance.web.public_ip
  target_platform = "unix"
}

# This only fires if an internal invariant is broken; ensure configs use
# parseConnectionInfo which validates target_platform to unix/windows.
# In HCL: target_platform = "unix" | "windows" (or omit).

// Go guard before quoting if constructing commands outside the helper:
func validTargetPlatform(p string) bool {
    return p == "unix" || p == "windows"
}

When it happens

Trigger: An explicit target_platform value that bypassed parseConnectionInfo's validation (e.g. set programmatically to 'mac', 'linux', or empty-but-not-defaulted through a non-standard path). Normally parseConnectionInfo defaults '' to unix and rejects anything else, so this is a defense-in-depth guard.

Common situations: A custom provisioner/communicator wrapper setting TargetPlatform directly; a malformed connectionInfo struct constructed outside parseConnectionInfo; a future code path that adds a platform constant without updating quoteScpCommand.

Related errors

• connection type '%s' not supported
• Error reading error message: %s
• Error creating temporary file for upload: %s
• host for provisioner cannot be empty
• target_platform for provisioner has to be either %s or %s

AI-assisted analysis of hashicorp/terraform@d32a084675 (2026-08-11). Data as JSON: /api/errors/7fa7e0aef063c122. Report an issue: GitHub.