#planet cassandra

[compdist-blog]

[Developer tutorial Part 3]

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Nota: el "</strong>" es una etiqueta HTML que se ha colado en el comando, por lo que hay que quitarlo para poder introducir ese mismo comando en cassandra.

[compdist-blog]

[Developer tutorial Part1] Configuration Directives

3 archivos principales de configuración:

Lets take a look at the three main configuration files for Apache Cassandra. To view the configuration files, from the root console type the following:

# cd /etc/cassandra

# ls 

Now we will look at each in more detail

cassandra.yaml

cassandra-env.sh

log4j-server.properties

The cassandra.yaml file is the main configuration file for Cassandra. After changing properties in this file, you must restart your instance for the changes to take effect. In this file, you can find properties to tune performance and system resource utilization (memory, disk I/O, CPU, etc.) for reads and writes. It also contains node and cluster initialization properties.

The cassandra-env.sh file in part controls the environment settings for Cassandra. It has heap sizing options(MAX_HEAP_SIZE, HEAP_NEWSIZE) and JMX options which can be monitored or manipulated, like nodetool, an JMX-compliment management tool. By default, JMX listens on port 7199 without authentication.

 If you are interested in configuring logging, you should look at the the log4j-server.properties file. In some situations, the output from nodetool utility is not enough to diagnose an issue. If you find that you need more information on runtime behavior of your instance, you can increase the logging levels to get more diagnostic information on specific portions of the system.

Podemos ver la información de cada archivo en la consola de root con el comando:

 # more cassandra.yaml

y podemos cambiarlos en un editor de texto.

para más información en los archivos de configuración:

http://wiki.apache.org/cassandra/StorageConfiguration

Ejemplo:

"Where are my keyspaces?"

LiveSchemaUpdates. You can load the schema once by using:

bin/schematool HOST PORT import

[datadio]

Datadio is a social tool to help marketers make better decisions through data analysis and communicating in real-time. - Rob Adler

http://www.planetcassandra.org/blog/post/social-media-aggregator-datadio-using-cassandra-to-expand-their-toolset