From 7842000f8a99b3010e60f9b7a73531e9a656ccd0 Mon Sep 17 00:00:00 2001
From: Nick Craig-Wood <nick@craig-wood.com>
Date: Wed, 24 May 2023 12:20:29 +0100
Subject: [PATCH] backend: for command not found errors, hint to look in the
 underlying remote

See: https://forum.rclone.org/t/rclone-cleanup-no-way-to-delete-pending-uploads-newer-than-24-hours/38416/6
---
 cmd/backend/backend.go | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/cmd/backend/backend.go b/cmd/backend/backend.go
index 67d499923..9a95a5e89 100644
--- a/cmd/backend/backend.go
+++ b/cmd/backend/backend.go
@@ -98,8 +98,14 @@ Note to run these commands on a running backend then see
 				out, err = doCommand(context.Background(), name, arg, opt)
 			}
 			if err != nil {
+				if err == fs.ErrorCommandNotFound {
+					extra := ""
+					if f.Features().Overlay {
+						extra = " (try the underlying remote)"
+					}
+					return fmt.Errorf("%q %w%s", name, err, extra)
+				}
 				return fmt.Errorf("command %q failed: %w", name, err)
-
 			}
 			// Output the result
 			writeJSON := false