diff --git a/HowtoCeph.md b/HowtoCeph.md
index 4143a476..f464965f 100644
--- a/HowtoCeph.md
+++ b/HowtoCeph.md
@@ -577,4 +577,11 @@ allouée *par pool* :
 
 ~~~
 ceph df
+~~~
+
+## création vm proprement
+
+~~~
+# apt install qemu-block-extra
+# qemu-img create -f raw rbd:rdb/bar 8
 ~~~
\ No newline at end of file