Enhanced JFS

Enhanced JFS, or JFS2, is another native AIX® journaling file system.

Enhanced JFS is the default file system for 64-bit kernel environments. Due to address space limitations of the 32–bit kernel, Enhanced JFS is not recommended for use in 32-bit kernel environments.

Support for data sets is integrated into JFS2 as part of the AIX operating system. A data set is a unit of data administration. It consists of a directory tree with at least one single root directory. Administration might include creating new data sets, creating and maintaining full copies (replicas) of data sets across a collection of servers, or moving a data set to another server. A data set might exist as a portion of a mounted file system. That is, a mounted file system instance might contain multiple data sets. Data set support is enabled in JFS2 by using the mkfs -o dm=on command. By default, data set support is not enabled. A data set enabled JFS2 instance can then be managed through the Dataset Services Manager (DSM).