Using FileSnaps

Table: provides a list of Veritas File System (VxFS) commands that enable you to administer FileSnaps.

Table:

Command

Functionality

fiostat

The fiostat command has the -S shared option to display statistics for each interval. Otherwise, the command displays the accumulated statistics for the entire time interval.

fsadm

The fsadm command has the -S option to report shared block usage in the file system. You can use this option to find out the storage savings achieved through FileSnaps and how much real storage is required if all of the files are full copies.

See the fsadm_vxfs(1M) manual page.

fsmap

The fsmap command has the -c option to report the count of the total number of physical blocks consumed by a file, and how many of those blocks might not be private to a given file.

See the fsmap(1) manual page.

mkfs

Use the mkfs command to make a disk layout Version 9 file system by specifying -o version=9. VxFS internally maintains a list of delayed operations on shared extent references and the size of this list (rcqsize) defaults to a value that is a function of the file system size, but can be changed when the file system is made.

See the mkfs_vxfs(1M) manual page.

vxfilesnap

Use the vxfilesnap command to create a snapshot of a file or set of files or files in a directory. You can also use the vxfilesnap command to restore a older version of the file to the current file.

See the vxfilesnap(1) manual page.

vxtunefs

The vxtunefs command supports an option to enable lazy copy-on-write tuneable, lazy_copyonwrite, on the file system, for better performance.

See the vxtunefs(1M) manual page.