acfsutil snap info

Purpose

Displays information about Oracle ACFS file system snapshots.

Syntax and Description

acfsutil snap info -h
acfsutil snap info -t [snapshot] mount_point

acfsutil snap info -h displays help text and exits.

Table 16-100 contains the options available with the acfsutil snap info command.

Table 16-100 Options for the acfsutil snap info command

Option	Description
`-t`	Displays a tree structure for the specified snapshot and mount point.
`snapshot`	Specifies a name for the snapshot.
`mount_point`	Specifies the directory where the file system is mounted.

The acfsutil snap info command displays information about an individual specified snapshot or all snapshots in the specified Oracle ACFS file system. The snapshot name, snapshot type (RO or RW), parent name, creation date and time, and space used are displayed. The parent name is either the mount point, or the parent snapshot if the snapshot was created from an existing snapshot.

The snapshot space usage amount includes snapshot metadata. If all the files are deleted from a snapshot, some metadata still remains and that amount is displayed with acfsutil snap info.

To reclaim the disk space used by snapshots, delete the snapshots. Deleting the files within the snapshots may not reclaim this disk space.

The acfsutil snap info command also shows pending delete operations.

Oracle ACFS caches and asynchronously updates snapshot storage usage statistics. If an Oracle ASM instance is killed, power is lost to the machine, or the Oracle ACFS file system goes offline for any reason, one of these cached updates may be lost. This loss can result in the display of a message similar to Reported snapshot space usage is inaccurate when acfsutil snap info is run.

Examples

Example 16-95 shows the use of the acfsutil snap info command on a Linux platform when there is a pending delete operation. When the background process finishes the clean up of the deleted snapshot, the delete pending row does not appear in the output.

Example 16-95 Using the acfsutil snap info command on Linux

$ /sbin/acfsutil snap info /acfsmounts/critical_apps
snapshot name:               midday_test2
RO snapshot or RW snapshot:  RW
parent name:                 /acfsmounts/critical_apps
snapshot creation time:      Fri Feb 18 06:10:59 2011

snapshot name:               payroll_report1
RO snapshot or RW snapshot:  RO
parent name:                 /acfsmounts/critical_apps
snapshot creation time:      Tue Feb 22 06:56:34 2011

snapshot name:               payroll_report2
RO snapshot or RW snapshot:  RO
parent name:                 /acfsmounts/critical_apps
snapshot creation time:      Tue Feb 22 06:57:21 2011

    number of snapshots:  3 (active)
                          1 (delete pending)
    snapshot space usage: 8383348736

Example 16-96 shows the use of the acfsutil snap info command on a Windows platform. These commands were run after the acfsutil snap create commands in Example 16-93.

Example 16-96 Using the acfsutil snap info command on Windows

$ /sbin/acfsutil snap info e:

snapshot name:               snap_1
RO snapshot or RW snapshot:  RW
parent name:                 e:
snapshot creation time:      Thu Oct 13 13:24:52 2011

snapshot name:               snap_1-1
RO snapshot or RW snapshot:  RW
parent name:                 snap_1
snapshot creation time:      Thu Oct 13 13:30:31 2011

    number of snapshots:  2
    snapshot space usage: 65536

$ /sbin/acfsutil snap info /t e:

e:                           RW
snap_1                       RW    e:
snap_1-1                     RW    snap_1

$ /sbin/acfsutil snap info /t snap1 e:

snap_1                       RW
snap_1-1                     RW    snap_1