Monitor the Cluster
ndb_mgm
Cluster Status
ndb_mgm> show
Data Node status
ndb_mgm> all status
Cluster Memory Usage
ndb_mgm> all report memory
How to Restart a MySQL Cluster without downtime
Start Management Cluster to reload configuration
ndb_mgmd --reload -f /var/lib/mysql-cluster/config.ini
Restart the management cluster
shell> kill $(pidof ndb_mgmd)
Starting the management cluster
shell> ndb_mgmd --config-file=var/lib/mysql-cluster/config.ini
#To restart ndb_mgmd overwritting cache files, the following options can be used on commandline (./ndb_mgmd)
--initial
--skip-config-cache
#or removing cache files with:
shell>rm -rf /var/lib/mysql-cluster/
#Data/Storage Node
The data or storage node, which is implements as ndbd or ndbmtf, handles data storage ans retrieval for specific subset of the cluster's data.
#Purpose of datanodes
to process and retrienve information, being the storage for the whole cluster
#Managing Data Node
Stop data node
ndb_mgm>
ndb_mgm> 3 STOP
#Starting Data Node
ndb_mgm> 3 START
Managing SQL Nodes
#Stop SQL Node
shell>service mysql stop
#Start SQL Node
shell>service mysql start
