Ext4 is the latest in a long line of Linux® file systems, and it's likely to be as important and popular as its predecessors. As a Linux system administrator, you should be aware of the advantages, disadvantages, and basic steps for migrating to ext4. This article explains when to adopt ext4, how to adapt traditional file system maintenance tool usage to ext4, and how to get the most out of the file system.
Linux supports several different file systems. Some are specialized network file systems or file systems developed for other operating systems, but a surprising number may be used as Linux native file systems—you can place your Linux root (/) and system directories on such file systems. Currently, file systems in this category include ext2, ext3, ReiserFS, XFS, and Journaled File System (JFS). However, file system design and development are ongoing, and new file systems are on the horizon.
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