This repository provides Hadoop in Docker containers. You can either run Hadoop in a single node or create a cluster.
The deployed Hadoop uses data replication "2". To change it edit the hdfs-site.xml file.
All data are stored in /hdfs-data, so to store data in a host directory run the container using "-v /path/to/host:/hdfs-data". By default the container formats the namenode directory only if not exists (hdfs namenode -format -nonInteractive). If you want to mount an external directory that already contains a namenode directory and format it you have to first delete it manually.
To deploy a single Hadoop node run
docker run -h namenode bde2020/hadoop-base
To store data in a host directory run the container as as
docker run -h namenode -v /path/to/host:/hdfs-data bde2020/hadoop-base
The namenode runs in a seperate container than the datanodes.
To start the namenode run
docker run --name namenode -h namenode bde2020/hadoop-namenode
To add a datanode to the cluster run
docker run --link namenode:namenode bde2020/hadoop-datanode
Use the same command to add more datanodes to the cluster
More info is comming soon on how to deploy a Hadoop cluster using docker network and docker swarm
The namenode listens on
hdfs://namenode:8020
To access the namenode from another container link it using "--link namenode:namenode" and then use the afformentioned URL. More info on how to access it using docker network coming soon.