5 1 0:Configuring a Media Pool
A media pool is a group of media of the same type that you use for backups. How you configure a media pool depends on the type of the used storage device. With loaders, you set up a media pool to be used for backups directly to tapes. For backing up to disks (disk storage), you have to set up a data store first, but still create a dedicated media pool(s) for it.
Once a media pool is configured, SEP sesam automatically labels each medium with a unique media label during initialization. The media labels are stored in the SEP sesam database. The labels consist of the pool name and a 5-digit number assigned by SEP sesam within the pool.
Media pools are the basis for building a backup strategy. Each media pool represents a set of media intended for a specific purpose. For example, media pools can be created and managed for workdays, weekends, specific locations, specific types, databases, etc. You can have different types of media pools for different types of backup data, backup sources (e.g., file backup, DB backup) or drive types.
You can assign a failover media pool to any media pool. In addition to media sharing (if these options are enabled) to ensure a media pool does not run out of media, a failover media pool can be used for backups or migration in case a media pool isn't available for writing for some reason (out of space, no free media, RDS cannot be reached).
It is possible to configure special GFS media pools for storing data on tape according to the GFS (Grandfather-Father-Son) retention strategy. For details, see GFS Backup Retention Strategy.
Note that the Options tab for configuring a special set of options to allow sharing of media across media pools is only available when configuring media pools for tape media, as described in the following section.
Configuring media pools for tape media
After you configure your backup hardware and create a new drive group, you have to create a new media pool and assign it to the drive group that contains your newly created drives. With loaders, you can configure a media pool that will be used for backing up directly to tapes. How you set up your backup strategy depends on the data that is being backed up. Typically, you would create at least three media pools. For details on setting up loaders and drives, see Configuring Loaders and Drives.
- From Main Selection -> Components -> Media Pools, click New Media Pool. The New Media Pool window opens.
- In the Media Pool window, specify the required fields:
- Name: Enter the name of a media pool, for example, MP_tape_day (for daily backups), MP_tape_week (for weekly backups), etc.
- Description: Optionally, add a description of the pool.
- Drive group: From the drop-down list of all available drive groups, select the relevant drive group to which a media pool will be attached (e.g, Tape_Drives, RDS_LTO_Dives, etc.). For details on drive groups, see Drives.
- Retention time [days]: Specify the retention time for the media pool. The retention time starts with the date a saveset is written to the media and lasts for the period defined by the media pool retention time (in days). The expiry date of the retention time is the EOL of the saveset. When a saveset is stored on a tape, every stored saveset has its own saveset EOL. However, the expiry date of the tape corresponds to the maximum retention time (the longest EOL) identified on it. For details, see tape media EOL.
- Failover media pool: Select a media pool to be used instead if this one is not available.
- Set media pool inactive: You can deactivate a media pool so that it is no longer available.
- Readability check limit [days]: By default, the value is 0 (zero) and the readability check is switched off. If you set a number > 0 , a tape is checked after the specified number of days and marked with the status Readability check needed. Note that the readability check can only be applied if the media EOL has not yet expired. It is not applicable to EOL-free media. For details, see Configuring a Readability Check.
- Expiration of read check overdue [days]: Specify the number of days after which a readability check is overdue. This calculation is based on the readability check limit [days] and the value of expiration overdue.
- Repeat rate for readability check [times]: If you select Unlimited, the media is checked according to the specified frequency. If you set Execute, the check is repeated as many times as specified.
|To perform the readability check, you have to set up a schedule and link a media event to it. When creating a media event, you have to select the readability check option and a media pool for your event. For details, see Configuring a Readability Check.|
Once you have created a media pool, you can set additional options. The Options tab is available in the media pool properties (Main Selection -> Components -> Media Pools -> double-click a media pool) and allows you to set up a media strategy and configure the sharing of media between media pools. This is useful when media from the target pool are not available for backup and another set of media can be used.
- May use empty, foreign media: SEP sesam will use unknown or blank tapes for the backup if no tapes are available in the respective pool.
- May use EOL free media: SEP sesam may use EOL-free media other than the requested one in a single tape drive (without loader).
- May use SPARE media: You have to configure a SPARE_ media pool (see the following section) and then you can enable the SPARE media option. This way, SEP sesam automatically uses the media from the SPARE pool if no tapes are available in the target media pool. For details, see Spare Pools.
- May use media from another pool: SEP sesam used available tapes from other media pools if no tapes are available in the target media pool.
- Another media pool may use media from this pool: A media pool that runs out of its own tapes can use the available tapes from this media pool.
- Close current backup tape before initializing new one: When you change to a new tape in this pool, the tape that is currently in use in this pool will be closed before a new one is initialized. With this option, the tape will get closed before it is offloaded from the tape drive, so that no more data can be appended to this tape.
If the data on the tapes is no longer needed, the metadata on the tape media in the media pools can be removed:
- Delete all metadata from tape media, once the tape becomes EOL free: Data on tapes can only be deleted when their EOL has expired. If you activate this option, the metadata of tapes that are no longer write-protected will be deleted.
- Delete all metadata of tape media and re-initialize the tape, once the tape becomes EOL free: If you activate this option, all metadata of the tape media is deleted and the tape is initialized (provided the tape is available to SEP sesam) by loading the tape into a drive and physically erasing it, thus removing access to all existing data on the tape.
For more details on tape-related operations, see Tape Management.
Configuring spare pools
You configure a spare pool in the same way as any other media pool, except for the name of the pool - SPARE_. The name of the spare pool must follow the rule to use SPARE_ as the naming convention. This way, SEP sesam is able to identify this pool as a spare pool.
Once your spare media pool is created, open its properties: Main Selection -> Components -> Media Pools -> double-click the spare media pool you created, switch to the Options tab and check the option Another media pool may use media from this pool. This means that any media pool that runs out of its own tapes can use the available tapes from this media pool.
Configuring media pools for data stores
With data stores, you configure media pools that are used for backing up to disks (disk storage). You must first configure a data store and then create a dedicated media pool for it. For details on how to configure a data store, see Configuring a Data Store.
- When you configure your data store, you are prompted to configure a media pool immediately. You can also configure a media pool later from the data store properties -> click Create Media Pool, or from Main Selection -> Components -> Media Pools, click New Media Pool. The New Media Pool window is displayed.
- Name: Enter the name of a media pool, e.g. DS_day (for daily backups), DS_week (for weekly backups), etc.
- Description: Optionally, add the description of the pool.
- Drive group: From the drop-down list of all available drive groups, select the relevant drive group to which a media pool will be attached (e.g, dg_datastore01). For details on the drive groups, see Drives.
- Retention time [days]: Specify the retention time for the media pool. The retention time for the media pool is specified in days and defines how long the data on the media remains protected. The retention time starts on the date a saveset is written to the media and lasts for the period defined by the media pool retention time (in days). The expiry date of the retention time is the EOL of the saveset. After the protection expires, the saveset is deleted while purge is running on the data store and the memory space is released. For details, see EOL (retention) types.
- Failover media pool: Select a media pool to be used instead if this one is not available.
- Click OK.
Monitoring data stores and configured media pools
You can check which media pools are configured with a data store in the GUI or via SEP sesam Web UI.
Data store properties in the Web UI
You can access the Web UI in one of the following ways:
- via the GUI: by clicking the Dashboard icon in the toolbar, or via the menu bar -> Activities -> Dashboard, or via Main Selection -> Monitoring and Reporting -> Dashboard
- by entering the following URL address in the browser bar:
- In the left menu, select Infrastructure -> Data stores and then click the name of the data store to display its properties.
- Check the configured media pools/media in section Media Pools, Media, Drives in Properties tab.
- Use the Dependencies tab to view the diagram of all dependencies of the datastore and Drives - RDS (first tab) or the datastore and Media Pools - Drive Groups - Drives - RDS (second tab). Hovering the cursor over the diagram shows a tooltip with details for each object.
Data store properties in the GUI
Open the data store properties: from Main Selection -> Components -> Data Stores -> double-click the selected data store -> select the Media tab. Click the media pool in the list to display its properties.
Media pools – Configuring Loaders and Drives – Configuring a Data Store – Managing EOL – Tape Management – GFS Backup Retention Strategy