Managing space

Edit online

You have methods for managing space in Copy Services Manager, including the Reflash After Recover option and the Free Journal Space command for sessions that contain Global Mirror relationships. You can also release space for FlashCopy targets after you terminate a session with space-efficient volumes.

About this task

The following two methods can assist with space management in Copy Services Manager on DS8000® storage systems for sessions that contain Global Mirror relationships:
Reflash After Recover option
Keeps a consistent copy of the data during a resync from the original site. This option is available when you create sessions and add properties to them. If you do not set the Reflash After Recover option, then the space is not used up.

See Using the Reflash After Recover option for more information.

Free Journal Space command
This command is available after a recover operation is performed for Global Mirror relationships. When the Reflash After Recover option is set, a FlashCopy relationship exists on the hardware. If the journal volume is a space-efficient volume, then the resync process might take up unnecessary back-end space, and fill up the repository. Use this command to delete the FlashCopy relationships from the hardware, which frees up the space.

See Using the Free Journal Space command for more information.

Note: The two options listed previously are not limited to Extent Space Efficient (ESE) volumes.
In addition, you have another option for managing space for any DS8000 sessions with FlashCopy relationships:
Releasing space if a Terminate or Remove Copy Set action does not automatically release the space:
Starting with V6.2.7, when you issue a Terminate command to the entire practice session, the session no longer automatically frees up space for FlashCopy targets for which the background copy has completed. This design helps prevent an accidental deletion of the FlashCopy target data if the copy had completed.
If you need to free the space after a Terminate, you can use the following DSCLI command to release the back-end repository:
dscli > init<fb|ckd>vol -action releasespace <volid>

where <volid> is the 4 digit volume ID.

Attention: The Copy Services Manager TerminateHxIx command will free the space even if the background copy has completed. If you issue the init or TerminateHxIx commands to free up the space, the data will no longer be accessible.

Using the Reflash After Recover option

Edit online

About this task

You can use the Reflash After Recover option from either the Copy Services Manager GUI or CLI.

Using the Reflash After Recover option from the GUI

Edit online

About this task

To choose the Reflash After Recover option from the GUI, complete the following steps:

Procedure

  1. Create a Copy Services Manager session and add copy sets to the session.
  2. On the Journal Options tab, select Reflash After Recover.

What to do next

After you set this option, a consistent copy of the data is kept during a resync from the original site. However, this action uses up journal space. Therefore, to free up journal space after the recover operation, see Using the Free Journal Space command.

Using the Reflash After Recover option from the CLI

Edit online

About this task

You can also set the Reflash After Recover option from the CLI.

Procedure

To set the Reflash After Recover option through the CLI, issue one of the following commands:
chsess -reflash yes <sessionName>
chsess -reflash no <sessionName>

For more information, see chsess. For more information, see the chsess command help topic in the Copy Services Manager online help documentation at https://www.ibm.com/support/knowledgecenter/SSESK4.

What to do next

After you set this option, a consistent copy of the data is kept during a resync from the original site. However, this action uses up journal space. Therefore, to free up journal space after the recover operation, see Using the Free Journal Space command.

Using the Free Journal Space command

Edit online

About this task

You can use the Free Journal Space command from either the Copy Services Manager GUI or CLI.

Using the Free Journal Space command from the GUI

Edit online

About this task

To use the Free Journal Space command from the GUI, complete the following steps:

Procedure

  1. Log in to the Copy Services Manager GUI as a user with administrative privileges.
  2. On the Sessions details page, select a session for which you want to free up the journal space.
  3. Click Session Actions > Commands > Free Journal Space.
    Note: The Free Journal Space command is only available after a recover operation is issued on the Global Mirror leg of the selected session.

Results

The FlashCopy relationships are deleted from the hardware, which frees up the journal space.

Using the Free Journal Space command from the CLI

Edit online

About this task

You can also issue the Free Journal Space command from the CLI.

Procedure

To free the journal space through the CLI, issue the following command:
cmdsess -action free_journal_space <sessionName>

For more information, see cmdsess. For more information, see the cmdsess command help topic in the Copy Services Manager online help documentation at https://www.ibm.com/support/knowledgecenter/SSESK4.

Results

The FlashCopy relationships are deleted from the hardware, which frees up the journal space.