This procedure shows how to upgrade a cluster of nodes from DataStax Community 1.0.x to DataStax Enterprise 2.1.x.
Perform these upgrade steps on each node in the cluster. Complete all steps on one node before starting to upgrade the next node.
To upgrade a node and migrate the data
Run nodetool drain to flush the commit log of the old installation:
cd <old Cassandra home>/bin ./nodetool drain –h <hostname>
Create a directory for the new installation, download the tarball, and move it to that directory.
Unpack the DataStax Enterprise 2.1.x tarball in the new install location.
tar –xzvf <dse-2.1.x tarball name>
If you customized the location of the data in the old installation, create a hard link to the old data directory:
cd <new install location> ln -s <old data directory> <new install location>/<new data directory>
To configure the upgraded node
In the new installation, open the cassandra.yaml for writing. The file is located in:
In the old installation of Cassandra, open the cassandra.yaml. The flle is located in:
Diff the new and old cassandra.yaml files.
Merge the diffs by hand from the old file into the new one, except do not merge snitch settings.
Configure the snitch setting and complete the configuration as described in Completing the Configuration and Starting Up the Upgraded Node.