diff --git a/ocaml/src/alba_test.ml b/ocaml/src/alba_test.ml
index e04ed8a1..60b42cb3 100644
--- a/ocaml/src/alba_test.ml
+++ b/ocaml/src/alba_test.ml
@@ -438,6 +438,17 @@ let test_clean_obsolete_keys () =
 
          assert_fragment ((=) None) >>= fun () ->
 
+         client # with_nsm_client'
+           ~namespace_id
+           (fun nsm ->
+            nsm # list_device_keys_to_be_deleted
+                ~first:"" ~finc:true
+                ~last:None
+                ~max:100 ~reverse:false
+                ~osd_id:osd_id_first_fragment) >>= fun r ->
+         Lwt_log.debug_f "%s" ([%show : string list] (r |> fst |> snd)) >>= fun () ->
+         assert (r = ((0, []), false));
+
          Lwt.return ()))
 
 let test_garbage_collect () =
diff --git a/ocaml/src/cli_nsm_host.ml b/ocaml/src/cli_nsm_host.ml
index 33a2bdae..3fa539ed 100644
--- a/ocaml/src/cli_nsm_host.ml
+++ b/ocaml/src/cli_nsm_host.ml
@@ -107,8 +107,69 @@ let list_device_objects_cmd =
   Term.info "dev-list-device-objects"
             ~doc:"objects from the namespace that have fragments on this device"
 
+
+let list_osd_keys_to_be_deleted
+      cfg_file tls_config
+      osd_id namespace_id
+      first finc max
+      reverse verbose
+  =
+  let t () =
+    with_alba_client
+      cfg_file
+      tls_config
+      (fun alba_client ->
+       alba_client # with_nsm_client'
+         ~namespace_id
+         (fun nsm_client ->
+          nsm_client # list_device_keys_to_be_deleted
+            ~osd_id
+            ~first ~finc ~last:None
+            ~max ~reverse
+          >>= fun ((cnt,xs), more) ->
+          Lwt_io.printlf "found %i items:" cnt >>= fun () ->
+          Lwt_list.iter_s
+            (Lwt_io.printlf "%s")
+            xs
+          >>= fun () ->
+          Lwt.return ()
+      ))
+  in
+  lwt_cmd_line ~to_json:false ~verbose t
+
+let list_osd_keys_to_be_deleted_cmd =
+  let osd_id default =
+    let doc = "osd's short id" in
+    Arg.(value
+         & opt int32 default
+         & info ["osd_id"] ~docv:"OSD_ID" ~doc)
+  in
+  let namespace_id default =
+    let doc = "namespace id" in
+    Arg.(value
+         & opt int32 default
+         & info ["namespace_id"] ~docv:"NAMESPACE_ID" ~doc)
+  in
+  let make_opt_bool name = Arg.(value & opt bool false & info [name]) in
+  let reverse = make_opt_bool "reverse" in
+  Term.(pure list_osd_keys_to_be_deleted
+        $ alba_cfg_url
+        $ tls_config
+        $ osd_id 0l
+        $ namespace_id 0l
+        $ first $ finc
+        $ max
+        $ reverse
+        $ verbose
+  ),
+  Term.info "dev-list-osd-keys-to-be-deleted"
+            ~doc:"list keys that have to be deleted"
+
+
+
 let cmds =
   [
     nsm_host_statistics_cmd;
     list_device_objects_cmd;
+    list_osd_keys_to_be_deleted_cmd;
   ]
diff --git a/ocaml/src/nsm_client.ml b/ocaml/src/nsm_client.ml
index 6c801388..8f192c57 100644
--- a/ocaml/src/nsm_client.ml
+++ b/ocaml/src/nsm_client.ml
@@ -121,7 +121,7 @@ class client (nsm_host_client : Nsm_host_client.basic_client) namespace_id =
         [(osd_id,
           List.map
             (fun key ->
-             Osd_keys.AlbaInstance.to_global_key namespace_id (key, 0, 0))
+             Osd_keys.AlbaInstance.to_global_key namespace_id (key, 0, String.length key))
             keys)]
 
     method get_gc_epochs =