MySQL Cluster work well but ndb_desc doesn't work

I have deployed and configured MySQL cluster. It works fine. -------------- ndb_mgm> show Connected to Management Server at: localhost:1186 Cluster Configuration [ndbd(NDB)]2 node(s) id=2@192.168.56.2 (mysql-5.6.19 ndb-7.3.6, Nodegroup: 0, *) id=3@192.168.56.3 (mysql-5.6.19 ndb-7.3.6, Nodegroup: 0) [ndb_mgmd(MGM)]1 node(s) id=1@192.168.56.1 (mysql-5.6.19 ndb-7.3.6) [mysqld(API)]1 node(s) id=4@192.168.56.4 (mysql-5.6.19 ndb-7.3.6) --------- I am reading the manual section about how to use MySQL cluster program http://dev.mysql.com/doc/refman/5.6/en/mysql-cluster-programs.html On SQL Node - 192.168.56.4, I am running: shell> ndb_desc -c 192.168.56.1 I receive message: Unable to connect to management server. NDBT_ProgramExit: 1 - Failed I did ping and telnet successful to management node - 192.168.56.1:1186 from sql node - 192.168.56.4 There is no firewall between them. What is cause of the problem ? Thank you in advance.