diff --git a/lib/fluent/plugin/in_tail.rb b/lib/fluent/plugin/in_tail.rb
index 88556ca6ab..09da75fcb1 100644
--- a/lib/fluent/plugin/in_tail.rb
+++ b/lib/fluent/plugin/in_tail.rb
@@ -526,6 +526,10 @@ def update_watcher(tail_watcher, pe, new_inode)
     # so adding close_io argument to avoid this problem.
     # At shutdown, IOHandler's io will be released automatically after detached the event loop
     def detach_watcher(tw, ino, close_io = true)
+      if @follow_inodes && tw.ino != ino
+        log.warn("detach_watcher could be detaching an unexpected tail_watcher with a different ino.",
+                  path: tw.path, actual_ino_in_tw: tw.ino, expect_ino_to_close: ino)
+      end
       tw.watchers.each do |watcher|
         event_loop_detach(watcher)
       end