Veritas File System 5.1 SP1 Administrator"s Guide (5900-1499, April 2011)

Mounting a file system with large files
If a mount succeeds and nolargefiles is specified, the file system cannot contain
or create any large files. If a mount succeeds and largefiles is specified, the file
system may contain and create large files.
The mount command fails if the specified largefiles|nolargefiles option does
not match the on-disk flag.
Because the mount command defaults to match the current setting of the on-disk
flag if specified without the largefiles or nolargefiles option, the best practice
is not to specify either option. After a file system is mounted, you can use the
fsadm utility to change the large files option.
Managing a file system with large files
Managing a file system with large files includes the following tasks:
■ Determining the current status of the large files flag
■ Switching capabilities on a mounted file system
■ Switching capabilities on an unmounted file system
To determine the current status of the largefiles flag, type either of the following
commands:
# mkfs -F vxfs -m special_device
# fsadm -F vxfs mount_point | special_device
To switch capabilities on a mounted file system:
# fsadm -F vxfs -o [no]largefiles mount_point
To switch capabilities on an unmounted file system:
# fsadm -F vxfs -o [no]largefiles special_device
You cannot change a file system to nolargefiles if it contains large files.
See the mount_vxfs(1M), fsadm_vxfs(1M), and mkfs_vxfs(1M) manual pages.
The cio option
The cio (Concurrent I/O) option specifies the file system to be mounted for
concurrent readers and writers. Concurrent I/O is a separately licensed feature
of VxFS. If cio is specified, but the feature is not licensed, the mount command
prints an error message and terminates the operation without mounting the file
system. The cio option cannot be disabled through a remount. To disable the cio
43VxFS performance: creating, mounting, and tuning file systems
Mounting a VxFS file system