The config_nodes table shows nodes configured in an NDB Cluster config.ini file. For each node, the table displays a row containing the node ID, the type of node (management node, data node, or API node), and the name or IP address of the host on which the node is configured to run.
This table does not indicate whether a given node is actually running, or whether it is currently connected to the cluster. Information about nodes connected to an NDB Cluster can be obtained from the nodes and processes table.
The config_nodes table contains the following columns:
node_id
The node's ID
node_type
The type of node
node_hostname
The name or IP address of the host on which the node resides
The node_id column shows the node ID used in the config.ini file for this node; if none is specified, the node ID that would be assigned automatically to this node is displayed.
The node_type column displays one of the following three values:
MGM: Management node.
NDB: Data node.
API: API node; this includes SQL nodes.
The node_hostname column shows the node host as specified in the config.ini file. This can be empty for an API node, if HostName has not been set in the cluster configuration file. If HostName has not been set for a data node in the configuration file, localhost is used here. localhost is also used if HostName has not been specified for a management node.