NDB Cluster Configuration Files Restart types.   Information about the restart types used by the parameter descriptions in this section is shown in the following table: Setting up a cluster using direct connections between data nodes requires specifying explicitly the crossover IP addresses of the data nodes so connected in the  [tcp]  section of the cluster  config.ini file. In the following example, we envision a cluster with at least four hosts, one each for a management server, an SQL node, and two data nodes. The cluster as a whole resides on the  172.23.72.*  subnet of a LAN. In addition to the usual network connections, the two data nodes are connected directly using a standard crossover cable, and communicate with one another directly using IP addresses in the  1.1.0.*  address range as shown: The  HostName1  and  HostName2  parameters are used only when specifying direct connections. 4225 # Management Server [ndb_mgmd] Id=1 HostName=172.23.72.20 # SQL Node [mysqld] Id=2 HostName=172.23.72.21 # Data Nodes [ndbd] Id=3 HostName=172.23.72.22 [ndbd] Id=4 HostName=172.23.72.23 # TCP/IP Connections [tcp] NodeId1=3 NodeId2=4 HostName1=1.1.0.1 HostName2=1.1.0.2 Table 23.21 NDB Cluster restart types Symbol Restart Type Description N Node The parameter can be updated using a rolling restart (see Section 23.5.5, “Performing a Rolling Restart of an NDB Cluster” ) S System All cluster nodes must be shut down completely, then restarted, to effect a change in this parameter I Initial Data nodes must be restarted using the  --initial  option 23.3.3.11 NDB Cluster TCP/IP Connections Using Direct Connections