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NAME

na_sis - Single Instance Storage (SIS) management.

SYNOPSIS

sis config [ [ -s schedule ] [ -C <true | false> ] [ -I <true | false> ] [ -Q <true | false> ] [ -z <file_size> ] path | path ... ]

sis on path

sis off path

sis start [ -s [ -p ] ] [ -f ] [ -d ] [ -m ] [ -o ] [ -q ] path

sis stop [ -a ] path

sis status [ -l ] [ [ path ] ... ]

sis revert_to [ <8.1> [ -delete ]] [ -cleanup ] [ path ]

DESCRIPTION

The sis command manages SIS operations: compression and/or deduplication. Data compression can be used on-the-fly, and/or as a scheduled background operation. This can be followed by deduplication, which is a method of reducing disk space usage by eliminating duplicate data blocks on a FlexVol volume, where only a single instance of each unique data blocks is stored.

The path parameter is the full path of a FlexVol volume, its format is /vol/vol_name.

The sis subcommands are:

config

This command is used to set up, modify, and retrieve the schedule or the options of a SIS enabled volume. Options can be retrieved and modified even after SIS is no longer enabled on a particular volume.

The -s option is used to set up or modify the schedule on the specified volume. If no option or path is specified, then the schedule of all configured SIS enabled volumes is displayed.

  schedule is [day_list][@hour_list]
        or [hour_list][@day_list]
        or -
        or auto
        or manual

The day_list specifies the days of the week that a SIS operation should run. It is a list of the first three letters of the day ( sun, mon, tue, wed, thu, fri, sat ) separated by a comma. Day ranges such as mon-fri can also be used. The default day_list is sun-sat. The names are not case sensitive.

The hour_list specifies the hours of each scheduled day that a SIS operation should run. The hour_list is from 0 to 23 separated by a comma. Hour ranges such as 8-17 are allowed. Step values can be used in conjunction with ranges (For example, 0-23/2 means every two hours in a day). The default hour_list is 0, i.e. at midnight of each scheduled day.

When SIS is enabled on a volume for the first time, an initial schedule is assigned to the volume. This initial schedule is sun-sat@0, which means run once every day at midnight.

If "-" is specified, no schedule is set on the volume. The auto schedule string triggers a SIS operation depending on the amount of new data written to the volume. The manual schedule string prevents SIS from automatically triggering any operations and disables change-logging. This schedule string can only be used on SnapVault destination volumes. The use of this schedule is mainly desirable when inline compression is enabled on a SnapVault destination volume and background processing is not necessary.

The config option -C is used to enable/disable compression. The default value is false.

The option -I is used to enable/disable inline compression. The default value is false. Inline compression can only be enabled if compression is enabled.

The config option -Q is used to enable/disable Incompressible Data Detection(IDD). The default value is false. IDD can be enabled only if compression is enabled.

The config option -z is used to set the minimum file size (in bytes), required for compression to attempt Quick Check on a file. The default value is 524288000.

on

The on command enables SIS operations on a volume. The specified volume must be an online FlexVol volume.

On a regular volume, SIS operations will be started periodically according to a per-volume schedule. On a SnapVault secondary volume, SIS operations will be triggered at the end of SnapVault transfers.

The schedule can be modified by the config subcommand. You can also manually start a SIS operation with the start subcommand.

off

The off command disables SIS operations on a volume. If a SIS operation is active on the volume, it needs to be stopped using sis stop before using the sis off command.

start

Use the start command to start SIS operations. The volume must be online and have SIS enabled before starting SIS operations. If there is a SIS operation already active on the volume, this command fails.

If the -s option is specified, the SIS operation scans the file system to process all the existing data. With the -s option, SIS operation prompts for user confirmation before proceeding. Use the -f option to suppress the confirmation. When the sis start command is issued, a checkpoint is created at the end of each stage or sub-stage, or on an hourly basis in the gathering phase. If at any point the sis start operation is stopped, the system can restart the SIS operation from the execution state saved in the checkpoint. The -d option can be used to delete the existing checkpoint and restart a fresh sis start operation. The checkpoint corresponding to gathering has a validity period of 24 hours. If the user knows that significant changes have not been made on the volume, then such a gatherer checkpoint whose validity has expired can be used with the help of the -sp option. There is no time restriction for checkpoints of other stages. In this release, whole volume scanning is supported on all FlexVol volumes. The -m option can be used to build the deduplication metadata by scanning the entire file system. You will not achieve any space savings with this option. Once the metadata is built, existing data can be shared with newly written data on subsequent deduplication runs. The -o option can be used to scan the entire file system and processes the shared blocks also. You can achieve additional space savings using this option. Where as the option -s saves some time by skipping the shared blocks.

Specifying the -q option will queue a new SIS operation.

The start command does not have any effect on inline compression.

stop

Use the stop command to abort any active SIS operations on the volume. SIS will remain enabled and the operations can be started again by using the start subcommand, SnapVault transfer, or the scheduler.

If the -a option is specified, both active and queued SIS operations are aborted.

status

Use the status command to report the status of SIS volumes. If one or more paths are specified, the command only displays the status of the specified volumes. The -l option will display detailed status, along with checkpoint information.

The df -s command displays the space savings generated by deduplication operations.

The df -S command displays the space savings generated by both compression and deduplication operations (see na_df(1)).

revert_to

This command downgrades SIS metafiles (fingerprint and changelog files) to Data ONTAP 8.1 release.

The -cleanup option deletes the previously downgraded SIS metafiles. This option does not take any Data ONTAP version number.

The -delete option deletes the existing SIS metafiles during ONTAP revert. When the revert_to command is run after setting this option, the existing SIS metafiles are not reverted, but deleted. After using this option, run sis start -s command on the downgraded ONTAP version to generate the SIS metafiles.

The -cleanup and -delete options are mutually exclusive.

With no options specified, the downgrade operation is done on the specified volume. If you do not specify the volume path, the operation is executed on all SIS enabled volumes.

When the sis revert_to command is run, a downgraded copy of the existing metafiles is created. Though the downgraded copy occupies extra disk space, the benefit of this approach is that if you decide not to proceed with the downgrade, then you can continue in the current version, which is also available after sis revert_to.

The sis start command on volumes that have downgraded metafiles does not succeed if there are previously downgraded metafiles. After executing the sis revert_to if you want to continue in the current version, clean up the reverted metafiles with -cleanup option. This reclaims the space occupied by the downgraded metafiles.

When general revert_to command is run and if a SIS enabled volume exists, it checks whether metafiles are downgraded or an option has been set to delete the current metafiles. If the check fails, you are prompted to downgrade the metafiles.

sis revert_to can be done only after SIS metafile upgrade to Data ONTAP 8.2 is completed. The sis start command can be run to upgrade the SIS metafiles.

Only after successful sis revert_to is done to the correct version, you can do a general revert_to. After a partial revert, the general revert_to does not succeed.

EXAMPLES

sis status

This command displays the status of all SIS enabled volumes. The following example shows the status output in short format:

  toaster> sis status
  Path                State       Status    Progress
  /vol/dvol_1         Enabled     Idle      Idle for 04:53:29
  /vol/dvol_2         Enabled     Pending   Idle for 15:23:41
  /vol/dvol_3         Disabled    Idle      Idle for 37:12:34
  /vol/dvol_4         Enabled     Active    25 GB Scanned
  /vol/dvol_5         Enabled     Active    25 MB Searched
  /vol/dvol_6         Enabled     Active    40 MB (20%) Done
  /vol/dvol_7         Enabled     Active    30 MB Verified
  /vol/dvol_8         Enabled     Active    10% Merged
  /vol/dvol_9         Enabled     Active    23 MB Scanned, 20 MB Compressed

The dvol_1 is Idle. The last SIS operation on the volume was finished 04:53:29 ago.

The dvol_2 is Pending for resource limitation. The SIS operation on the volume will become Active when the resource is available.

The dvol_3 is Idle because the SIS operation is disabled on the volume.

The dvol_4 is Active. The SIS operation is doing whole volume scanning. So far, it has scanned 25GB of data.

The dvol_5 is Active. The operation is searching for SIS data, there are 25MB of data already searched.

The dvol_6 is also Active. The operation has saved 40MB of data. This is 20% of the total SIS data found in the searching stage.

The dvol_7 is Active. It is verifying the metadata of processed data blocks. This process will remove unused metadata.

The dvol_8 is Active. Verified metadata is being merged. This process will merge together all verified metadata of processed data blocks to an internal format which supports fast SIS operation.

The dvol_9 is Active. The operation is scanning the volume and so far it has compressed 20MB of data.

The following examples show the sis status output in long format:

         toaster> sis status -l /vol/dvol_1

         Path:                                   /vol/dvol_1
         State:                                  Enabled
         Compression:                            Enabled
         Inline Compression:                     Enabled
         Incompressible Data Detection:          Disabled
         Compression Quick Check File Size:      524288000
         Status:                                 Idle
         Progress:                               Idle for 04:54:34
         Type:                                   Regular
         Schedule:                               -
         Minimum Blocks Shared:                  1
         Blocks Skipped Sharing:                 0
         Last Operation State:                   Failure
         Last Successful Operation Begin:        Fri Jul 30 18:03:40 GMT 2010
         Last Successful Operation End:          Fri Jul 30 18:04:20 GMT 2010
         Last Operation Begin:                   Fri Jul 30 18:08:40 GMT 2010
         Last Operation End:                     Fri Jul 30 18:08:55 GMT 2010
         Last Operation Size:                    0 KB
         Last Operation Error:                   Operation was stopped
         Changelog Usage:                        0%
         Checkpoint Time:                        Fri Jul 30 18:08:55 GMT 2010
         Checkpoint Op Type:                     Scan
         Checkpoint Stage:                       Sorting
         Checkpoint Sub-stage:                   -
         Checkpoint Progress:                    0 KB Searched
         Logical Data:                           502 MB/62 TB (0%)
         Queued Job:                             -
         Stale Fingerprints:                     0%


         toaster> sis status -l /vol/dvol_9

         Path:                                   /vol/dvol_9
         State:                                  Enabled
         Compression:                            Enabled
         Inline Compression:                     Enabled
         Incompressible Data Detection:          Disabled
         Compression Quick Check File Size:      524288000
         Status:                                 Active
         Progress:                               512000 KB Scanned, 447740 KB Compressed
         Type:                                   Regular
         Schedule:                               -
         Minimum Blocks Shared:                  1
         Blocks Skipped Sharing:                 0
         Last Operation State:                   Success
         Last Successful Operation Begin:        Fri Jul 30 18:13:20 GMT 2010
         Last Successful Operation End:          Fri Jul 30 18:13:20 GMT 2010
         Last Operation Begin:                   Fri Jul 30 18:13:20 GMT 2010
         Last Operation End:                     Fri Jul 30 18:13:20 GMT 2010
         Last Operation Size:                    0 KB
         Last Operation Error:                   -
         Changelog Usage:                        0%
         Checkpoint Time:                        No Checkpoint
         Checkpoint Op Type:                     -
         Checkpoint Stage:                       -
         Checkpoint Sub-stage:                   -
         Checkpoint Progress:                    -
         Logical Data:                           502 MB/62 TB (0%)
         Queued Job:                             -
         Stale Fingerprints:                     0%

Path: The absolute path of the volume.

State: The current state of SIS on the volume (Enabled or Disabled).

Compression: The current state of compression on the volume (Enabled or Disabled).

Inline Compression: The current state of inline compression on the volume (Enabled or Disabled).

Incompressible Data Detection: The current state of incompressible data detection on the volume (Enabled or Disabled).

Compression Quick Check File Size: The minimum file size (in bytes) required to attempt Quick check on the file. The default value is 500MB and can be changed using sis config command.

Status: The status of the SIS operation on the volume.

Progress: The progress of the SIS operation on the volume.

Type: The type of SIS volume.

Schedule: The schedule of SIS operation for the volume.

Minimum Blocks Shared: The minimum number of adjacent blocks in a file that can be shared.

Blocks Skipped Sharing: The number of blocks skipped in the deduplication process.

Last Operation Status: The status of the last operation.

Last Successful Operation Begin: The time and date at which the last successful operation began.

Last Successful Operation End: The time and date at which the last successful operation ended.

Last Operation Begin: The time and date at which the last operation began.

Last Operation End: The time and date at which the last operation ended.

Last Operation Size: The size of the last operation.

Last Operation Error: The error encountered by the last operation.

Changelog Usage: The percentage of the changelog that was used.

Checkpoint Time: The time and date at which the checkpoint was created.

Checkpoint Op Type: The operation during which the checkpoint was created.

Checkpoint Stage: The stage of operation at which the checkpoint was created.

Checkpoint Sub-stage: The sub-stage of the checkpoint stage.

Checkpoint Progress: The progress of the checkpoint.

Logical Data: The total logical data in the volume, and how much is reached compared to the deduplication logical data limit, displayed as Logical Data Size / Logical Data limit (Logical Data percent).

Queued Job: The job that is queued.

Stale Fingerprints: The percentage of stales in fingerprint database. If this is > 20%, subsequent `sis start' operation triggers the verify operation, which may take a long time to complete.

sis config

This command displays the schedule and compression configuration for all SIS enabled volumes. The following example shows the config output:

    toaster> sis config
                                                  Inline      Incompressible Compression Quick
    Path                 Schedule     Compression Compression Data Detection Check File Size
    -------------------- ------------ ----------- ----------- -------------- -----------------
    /vol/dvol_1          -            Enabled     Enabled     Disabled       524288000
    /vol/dvol_2          23@sun-fri   Enabled     Disabled    Enabled        524288000
    /vol/dvol_3          auto         Disabled    Disabled    Disabled       524288000

SIS on the volume dvol_1 is not scheduled.

SIS on the volume dvol_2 is scheduled to run every day from Sunday to Friday at 11 PM.

SIS on the volume dvol_3 is set to auto schedule.

sis revert_to

This command downgrades SIS metafiles.

sis revert_to 8.1

Downgrades the SIS metafiles on all SIS enabled volumes.

sis revert_to -cleanup

Deletes all of the downgraded metafiles created, if they exist.

sis revert_to 8.1 -delete

Ensures that all the current versions of SIS metafiles are deleted when the Data ONTAP revert_to command is run. In such a case, the SIS metafiles are not downgraded.

sis revert_to 8.1 /vol/vol1

Downgrades the SIS metafiles on volume vol1.

SEE ALSO

na_df(1)


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