document existence of document_thumbnails

diff --git a/docs/administration.md b/docs/administration.md
index 4daa446c50daf0e037260d444e6ab2e553a95504..ee6a9a02c4ef337e1fe9f9de53e68ef4c47fdb24 100644 (file)
--- a/docs/administration.md
+++ b/docs/administration.md
@@ -353,6 +353,14 @@ document_create_classifier
 
 This command takes no arguments.
 
+### Document thumbnails {#thumbnails}
+
+Sometimes you may wish to re-create document thumbnails. Use
+
+```
+document_thumbnails
+```
+
 ### Managing the document search index {#index}
 
 The document search index is responsible for delivering search results