Tape pools

Acronis Backup uses tape pools that are logical groups of tapes. Only one pool is associated with each vault, and all operations with the vault are applicable only to the tapes in the respective pool. The software contains the following predefined tape pools: Unrecognized tapes, Imported tapes, Free tapes, and Acronis. Also, you can create your own custom pools.

Tape vaults

A vault is a location for storing backup archives. For ease of use and administration, a vault is associated with the archives' metadata. Referring to this metadata makes for fast and convenient operations with archives and backups stored in the vault.

Tape sets

Tape sets can be activated in tape management backup options. The option applies to backing up to a storage node. Tapes within one pool can be grouped into so-called tape sets. If you leave this option disabled, data from different machines will be backed up on all tapes belonging to a pool. If the option is enabled, backups of each machine will be stored on a separate tape set.

Inventory

The inventorying operation detects tapes loaded into a tape device and assigns names to those that have none. Perform the operation every time you load tapes into the tape device slots.

Acronis Backup Advanced uses three parameters to identify tape: barcode, data on tape and its serial number.

• Barcode is taken from barcode reader inside autoloader. 
• Serial number reads from internal tape memory. Tape memory is accessed only during full inventory.
• If tape store non acronis data then for identification first kilobyte is read . For acronis tapes there is a special tape header on the tape.

Problems may appear when all three parameters are empty or inaccessible. For example when using a new tape. If a tape had been used for backup then acronis should identify it unambiguously.

Fast inventorying

Acronis Backup scans tapes for barcodes. Using barcodes, the software can quickly return a tape to the pool where it was before.
Select this method to recognize tapes used by the same tape device attached to the same machine. Other tapes will be sent to the Unrecognized tapes pool.
If your tape library contains no barcode reader, all tapes will be sent to the Unrecognized tapes pool. To recognize your tapes, perform full inventorying or combine fast and full inventorying as described later in this section.

Full inventorying

Acronis Backup reads tags written by Acronis software and analyzes other information about the contents of the loaded tapes. Select this method to recognize empty tapes and tapes written by Acronis software on any tape device and any machine.

Retention

Retention rules are specified within a backup plan and generally define how to delete or move the backups created by this plan. From tape vaults retention rules cannot move backups to further locations. When retention rules are applied to an archive, the backup that should be retained is not deleted from the tape, but is marked for deletion with a trash icon. Tape is never cleaned by the retention rules and the backups are not physically removed from tapes or tape database.

Cleaning up backups from tapes and tape database

In order to completely remove information about a backup from the vault, tape database and TapeLocation folder, tape with this backup should be  erased, removed or overwritten. Thus the only way that backup data is cleaned up automatically, is that the tape containing this backup is overwritten by a new backup. Conditions for a tape to be overwritten are the following:

• Every backup on the tape is marked for deletion.
• All dependent backups on other tapes (differential and incremental) become subject to deletion as well.

Moving tapes to Free tapes pool

When you move a tape to the Free tapes pool, the software marks it as empty. If the tape contains backups, they are marked with the trash icon. When the software starts overwriting the tape, the data related to the backups will be removed from the database.

Supplementary files (TapeLocation folder)

Upon each backup the software creates supplementary files on a hard disk of the machine where the tape device is attached. File recovery from disk backups is possible as long as these supplementary files are intact. The files are deleted automatically when the tape storing the respective backups is erased, removed or overwritten.

The supplementary files' locations are as follows:

• In Windows XP and Server 2003: %ALLUSERSPROFILE%\Application Data\Acronis\BackupAndRecovery\TapeLocation.
• In Windows Vista and later versions of Windows: %PROGRAMDATA%\Acronis\BackupAndRecovery\TapeLocation.
• In Linux: /var/lib/Acronis/BackupAndRecovery/TapeLocation.

The space occupied by these supplementary files depends on the number of files in the respective backup. For a full backup of a disk containing approximately 20,000 files (the typical workstation disk backup), the supplementary files occupy around 150 MB. A full backup of a server containing 250,000 files may produce around 700 MB of supplementary files.

 

Read following instructions to avoid lack of free tapes during backup and adjust you backup strategy accordingly.

1. Select the minimum retention period

If you want to keep backups at least for 1 week, the retention period will be 1 week. Set this period for retention rules in the backup plans.

Example: I choose the retention period of 2 weeks.

2. Identify the maximum number of versions that can fit on the given number of tapes

Create 1 full, 1 differential or 1 incremental backup for each machine or backup plan depending on what type of backup you are planning to use.

Calculate how many versions of full backups or diff/incr backups will fill on the given number of tapes.

Example: I have 2 servers, SRV1 full is 150GB, SRV1 increment is 10 GB, SRV2 full is 230GB, SRV2 increment is 15Gb. I use LTO4 with 800GB storage size. It can store 800/(150+230)=2 full versions or 800/(10+15)=32 incremental versions on 1 tape. I have 4 tapes, so I can have 8 full or 128 incremental backup versions.

3. Choose the number of backup versions for the selected retention period

One retention period contains at least 1 full backup and may contain 1 or more diff/incr backups.

Example: I need to create 1 full backup weekly and 1 incremental backup daily. So 1 retention period will contain 2 full and 12 incremental backups.

4. Calculate the mutual size of all backups for the selected retention period

Mutual size is calculated for all machines or backup plan sources.

Example: 2 full and 12 incremental backups are 1060GB.

5. Calculate the number of tapes required for 1 retention period (retention tape set)

All backups for one retention period must fit on the selected number of tapes.

If an option Use a separate tape set for each single machine or Always use a free tape is selected, the minimum number of tapes will be equal to the number of full backups.

If you specify more than 1 tape drive in the vault and run parallel backup to that vault, number of tapes can be more than required for that amount of data since tapes are used simultaneously.

Example: I don't need to split backups to different tapes, so I will calculate the whole tape space size. For 1 retention period (1060GB) I need 2 tapes.

6. Calculate the available number of retention tape sets

Divide the number of all available tapes by the number of tapes in one retention tape set.

Example: I have 4 tapes, and 2 tapes are required for 1 retention period. So I have 2 retention tape sets.

7. Calculate the number of retention periods that can be placed on one retention tape set (fully or partly)

If backups from the first retention period do not fill the tape completely, backups from next retention period will be placed to the same tapes until they are fully written.

If an option Always use a free tape is selected For each full backup is enabled in all backup plans, the number of retention periods is always 1.

Example: 2 tapes from 1 retention set will contain 1060GB from the first retention period and 470GB from the second retention period. So the number is 2.

8. Evaluate the results

The sum of number of retention periods on one retention tape set and the number of retention tape sets must not be less than 5, and each of them must not be less than 2. Then the retention will be performed without problems with 1 vault and 1 pool setup.

In case both number of retention periods on one retention tape set and the number of retention tape sets are equal 2, divide the tapes in 2 pools equally, create 1 vault for each pool and 2 sets of backup plans. Backup plans' schedules should alternate each retention period.

In case there are tapes for less than 2 retention tape sets, consider reducing number of backup versions to increase the number of retention tape sets. If this is not possible, move tapes to Free tapes after a number of backups manually. The pool must also take tapes from Free tapes pool (pool settings).

Example: I have 2 retention tape sets and 2 retention periods can be placed on one retention tape set, so the sum is 4. This is the strategy I will apply. Backup plan 1 for 2 first weeks will backup to the first vault and will use 2 tapes from first pool. Backup plan 2 for 2 second weeks will backup to the second vault and will use 2 tapes from second pool.

 Select the appropriate issue and complete the troubleshooting steps.

2.1 Issue with pools

Tapes are not used after being moved to a custom pool upon specified condition

One vault is associated with only 1 pool. In case the final custom pool (where the tape is moved to) is not associated with any vault, tapes from this pool will not be used, retained or cleaned. To retain tapes from this pool, create a new vault that will use tapes from this pool, or specify this pool in the existing vault. Otherwise move the tape from this pool to other used pool manually.

I want to create full backups on one set of tapes, and incremental backups on other set of tapes. I created two pools and two vaults for this, but fulls are created instead of incrementals.

Incremental backups can be created only as increment to a full backup in the same archive. One archive can be placed only in 1 vault. When you start an incremental to an empty vault, a full backup is created automatically. In order to place incremental backups on a separate set of tapes, backup to 1 vault and use one of the following options:

• Use GFS or Tower of Hanoi scheme. These schemes automatically device backups to tapes according to the type of the backup.
• After full backup, move the tapes with full backups to a custom pool. Exchange the tapes with incremental backups and full backups manually on every backup.
• In backup settings check the "Always use a free tape for each incremental backup" tape option. You will need 1 tape for each full and incremental backup.

2.2 Issue with tape drives usage

 I have 2 tape drives and have several machines backing up simultaneously. However only one drive is used during backup.

Edit the tape vault settings and specify both tape drives for usage in this vault.

I have 2 tape drives and I want to backup one machine to 2 drives simultaneously. However only one drive is used during backup.

This behavior is expected. Backup is written to tape as a stream and can span across several tapes only when the first tape is full.

2.3 Issue with cleanup

All my backups are marked for deletion, but the TapeLocation folder is still large and data is not removed.

This behavior is expected. TapeLocation folder is cleaned up when the tape with respective backups is overwritten, cleaned or moved to Free tapes pool.

All backup on tape 1 are marked for deletion, but next backup starts to a new media and does not overwrite tape 1.

Backups on tape 1 have dependencies on other tapes that are not yet marked for deletion. Go to Tame Management view and see dependent backups for this tape.

If all steps above have been performed and issue still persists, go to collect information step.

 

 

Collect following information and contact Acronis Support.

3.1 Issue description

 Provide the issue description with screenshots of following components:

• Tape Management -> Select a pool -> Click on Details and make screenshots of pool details and tapes in this pool. Repeat for every pool.
• Tape Management -> Click on Inventory -> Select Full -> Expand all devices and make screenshots of drives and slots.
• Vaults -> Select the vault -> Edit -> Make a screenshot of vault settings with pool and tape drives details.
• Export the backup plan as XML file.

3.2 System Report

Collect system information from the machine with the tape drive installed:

•  Acronis Backup 11.5: Generating System Report

3.3 Tape Tools

Depending on the nature of issue:

• Tape Compatibility Tool output
• Tape Detection Tools outputs