allow skipping roles without directory

startup.sh

@@ -7,6 +7,10 @@ cd client
 HOSTNAME="$HOSTNAME" docker-compose up -d
 cd -
 
+
+# allow empty match on * to prevent manual check if role_dir and osd_dir exists
+shopt -s nullglob
+
 #bring up mon, mds, mgr
 for role_dir in /ceph/m*; do
     role_name=$(basename "$role_dir")