ECS 3.6.2 Data Access Guide

Multi-protocol (cross-head) access

ECS supports the ability to write data to a bucket using the S3 protocol and to make that data available as files through HDFS.

Multi-protocol access (also referred to as cross-head access) means objects written to the bucket using the S3 protocol can become the subject of Hadoop jobs, such as MapReduce. Similarly, directories and files written by HDFS can be read and modified using S3 clients.

In order that data written using S3 can be accessed as files, the bucket administrator can set a Default Group on the bucket and can set default permissions for files and directories owned by that group. This default Unix group is assigned to objects when they are created from S3 so that they have an owner and have group membership and group permissions that enable HDFS access from the Hadoop cluster.

Files created using HDFS and accessed using the S3 protocol are not affected by the default permissions as they are only applied to objects created using the S3 protocol.