Quickstart (1.x)

Installing Accumulo

This document covers installing Accumulo on single and multi-node environments. Either download or build a binary distribution of Accumulo from source code. Unpack as follows:

cd <install_location>
tar xzf <some_dir>/accumulo-X.Y.Z-bin.tar.gz
cd accumulo-X.Y.Z

Accumulo has some optional native code that improves its performance and stability. Before configuring Accumulo attempt to build this native code with the following command.

./bin/build_native_library.sh

If the command fails, its ok to continue with setup and resolve the issue later.

Configuring

The Accumulo conf directory needs to be populated with initial config files. The following script is provided to assist with this. Run the script and answer the questions. When the script ask about memory-map type, choose Native if the build native script was successful. Otherwise choose Java.

./bin/bootstrap_config.sh

The script will prompt for memory usage. Please note that the footprints are only for the Accumulo system processes, so ample space should be left for other processes like hadoop, zookeeper, and the accumulo client code. If Accumulo worker processes are swapped out and unresponsive, they may be killed.

After this script runs, the conf directory should be populated and now a few edits are needed.

Secret

Accumulo coordination and worker processes can only communicate with each other if they share the same secret key. To change the secret key set instance.secret in conf/accumulo-site.xml. Changing this secret key from the default is highly recommended.

Dependencies

Accumulo requires running Zookeeper and HDFS instances. Also, the Accumulo binary distribution does not include jars for Zookeeper and Hadoop. When configuring Accumulo the following information about these dependencies must be provided.

  • Location of Zookeepers : Provide this by setting instance.zookeeper.host in conf/accumulo-site.xml.
  • Where to store data : Provide this by setting instance.volumes in conf/accumulo-site.xml. If your namenode is running at 192.168.1.9:9000 and you want to store data in /accumulo in HDFS, then set instance.volumes to hdfs://192.168.1.9:9000/accumulo.
  • Location of Zoookeeper and Hadoop jars : Setting ZOOKEEPER_HOME and HADOOP_PREFIX in conf/accumulo-env.sh will help Accumulo find these jars.

If Accumulo has problems later on finding jars, then run bin/accumulo classpath to print out info about where Accumulo is finding jars. If the settings mentioned above are correct, then inspect general.classpaths in conf/accumulo-site.xml.

Initialization

Accumulo needs to initialize the locations where it stores data in Zookeeper and HDFS. The following command will do this.

./bin/accumulo init

The initialization command will prompt for the following information:

  • Instance name : This is the name of the Accumulo instance and its Accumulo clients need to know it inorder to connect.
  • Root password : Initialization sets up an initial Accumulo root user and prompts for its password. This information will be needed to later connect to Accumulo.

Multiple Nodes

Skip this section if running Accumulo on a single node. Accumulo has coordinating, monitoring, and worker processes that run on specified nodes in the cluster. The following files should be populated with a newline separated list of node names. Must change from localhost.

  • conf/masters : Accumulo primary coordinating process. Must specify one node. Can specify a few for fault tolerance.
  • conf/gc : Accumulo garbage collector. Must specify one node. Can specify a few for fault tolerance.
  • conf/monitor : Node where Accumulo monitoring web server is run.
  • conf/slaves : Accumulo worker processes. List all of the nodes where tablet servers should run in this file.
  • conf/tracers : Optional capability. Can specify zero or more nodes.

The Accumulo, Hadoop, and Zookeeper software should be present at the same location on every node. Also the files in the conf directory must be copied to every node. There are many ways to replicate the software and configuration, two possible tools that can help replicate software and/or config are pdcp and prsync.

Starting Accumulo

The Accumulo scripts use ssh to start processes on remote nodes. Before attempting to start Accumulo, passwordless ssh must be setup on the cluster.

After configuring and initializing Accumulo, use the following command to start it.

./bin/start-all.sh

First steps

Once the start-all.sh script completes, use the following command to run the Accumulo shell.

./bin/accumulo shell -u root

Use your web browser to connect the Accumulo monitor page on port 9995.

http://<hostname in conf/monitor>:9995/

When finished, use the following command to stop Accumulo.

./bin/stop-all.sh