Prerequisites¶
This guide details the prerequisites required to run Pravega in production (Distributed mode only).
HDFS¶
Setup an HDFS storage cluster running HDFS version 2.7+. HDFS is used as Tier 2 storage and must have sufficient capacity to store contents of all streams. The storage cluster is recommended to be run alongside Pravega on separate nodes.
Java¶
Install the latest Java 8 from java.oracle.com. Packages are available for all major operating systems.
Zookeeper¶
Pravega requires Zookeeper 3.5.1-alpha+. At least 3 Zookeeper nodes are recommended for a quorum. No special configuration is required for Zookeeper but it is recommended to use a dedicated cluster for Pravega.
This specific version of Zookeeper can be downloaded from Apache at zookeeper-3.5.1-alpha.tar.gz.
For installing Zookeeper see the Getting Started Guide.
Bookkeeper¶
Pravega requires Bookkeeper 4.4.0+. At least 3 Bookkeeper servers are recommended for a quorum.
This specific version of Bookkeeper can be downloaded from Apache at bookkeeper-server-4.4.0-bin.tar.gz.
For installing Bookkeeper see the Getting Started Guide.
Some specific Pravega instructions are shown below. All sets assuming being run from the bookkeeper-server-4.4.0
directory.
Bookkeeper Configuration¶
The following configuration options should be changed in the conf/bk_server.conf
file.
# Comma separated list of <zp-ip>:<port> for all ZK servers zkServers=localhost:2181 # Alternatively specify a different path to the storage for /bk journalDirectory=/bk/journal ledgerDirectories=/bk/ledgers indexDirectories=/bk/index zkLedgersRootPath=/pravega/bookkeeper/ledgers
Initializing Zookeeper paths¶
The following paths need to be created in Zookeeper. From the zookeeper-3.5.1-alpha
directory on the Zookeeper servers run:
bin/zkCli.sh -server $ZK_URL create /pravega bin/zkCli.sh -server $ZK_URL create /pravega/bookkeeper
Running Bookkeeper¶
Before starting the bookie, it needs to be formatted:
bin/bookkeeper shell metaformat -nonInteractive
Start the bookie:
bin/bookkeeper bookie