About Veritas File System disk layouts

The disk layout is the way file system information is stored on disk. On Veritas File System (VxFS), several different disk layout versions were created to take advantage of evolving technological developments.

The disk layout versions used on VxFS are:

Version 6

Version 6 disk layout enables features such as multi-volume support, cross-platform data sharing, named data streams, and File Change Log.

A disk layout Version 6 file system can still be mounted, but this will be disallowed in future releases. Symantec recommends that you upgrade from Version 6 to the latest default disk layout version. In this release, disk layout Version 6 cannot be cluster mounted. You cannot create new file systems with disk layout Version 6. The only operation that you can perform on a file system with disk layout Version 6 is to upgrade the disk layout to a supported version. If you upgrade a file system from disk layout Version 6 to a later version, once the upgrade operation finishes, you must unmount the file system cleanly, then re-mount the file system.


Version 7

Version 7 disk layout enables support for variable and large size history log records, more than 2048 volumes, large directory hash, and SmartTier.


Version 8

Version 8 disk layout enables support for file-level snapshots.


Version 9

Version 9 disk layout enables support for file compression, file replication, data deduplication, and partition directories.


Version 10

Version 10 disk layout enables support for SmartIO and maxlink.


Some of the disk layout versions were not supported on all UNIX operating systems. Currently, only the Version 7, 8, 9, and 10 disk layouts can be created and mounted. The Version 6 disk layout can be mounted, but only for upgrading to a supported version. Disk layout Version 6 cannot be cluster mounted. To cluster mount such a file system, you must first mount the file system on one node and then upgrade to a supported disk layout version using the vxupgrade command. No other versions can be created or mounted. Version 10 is the default disk layout version.

The vxupgrade command is provided to upgrade an existing VxFS file system to the Version 10 layout while the file system remains online.

See the vxupgrade(1M) manual page.

The vxfsconvert command is provided to upgrade ext2 or ext3 file systems to the Version 10 disk layout while the file system is not mounted.

See the vxfsconvert(1M) manual page.