Friday, September 17, 2010

Moving from version 0.6 of Cassandra to version 0.7

In order to use the latest build of Hector you need to be running a cluster based on version 0.7 of Cassandra. For me this gave me some problems. For a start I’m running my cluster on windows based machines, and it’s been running fine. However beta 1 of Cassandra 0.7.0 does not include the necessary tools for windows to convert the config files and read the schema.

So to get my cluster updated I added a linux box to it and installed a version 0.6.0 of Cassandra and joined the cluster. I installed 0.7.0 on that and attempted to use config-convertor to convert storage-conf.xml to Cassandra.yaml. For some reason that got in a horrible mess so it was back to the original Cassandra.yaml and import the settings manually. For my simple configuration this wasn’t a pain.

Once that’s done I upgraded the windows machines to version 0.7.0.

The next step is to run schematool. Without running this, your cluster will not have any schema’s in the database. This needs to be done from the linux command line:

schematool 134.36.xx.yyy 8080 import

does the job.

See http://www.riptano.com/blog/live-schema-updates-cassandra-07 and http://wiki.apache.org/cassandra/LiveSchemaUpdates for more details.