Unable to connect with connect string: nodeid=0,localhost:1186 (no replies)

Good morning everyone,
While configuring a cluster (4 data nodes, 1 mgm node, 1 sql node) with MYSQL CLUSTER MANAGER I'm facing the following error:

mysql@data2:~> ndb_mgm
-- NDB Cluster -- Management Client --
ndb_mgm> show
Unable to connect with connect string: nodeid=0,localhost:1186
Retrying every 5 seconds. Attempts left: 2

The problem is I don't know where to set the option "connect string" for data nodes (using MySQL Cluster Manager). Any ideas?

Kind regards,
Gabriel