FlashCopy — Main page

Introduction

A FlashCopy relationship cannot be established between volumes of different storage types. For example, if you select a fixed block (FB) volume as a source volume, the page that is displayed for target volume selection does not display any count-key-data (CKD) volumes. A source volume can participate in a maximum of twelve FlashCopy relationships at one time. The source volume cannot be a target volume for another relationship.

The FlashCopy feature is accessible only from the Real-time Manager; the FlashCopy feature is not accessible from the Simulated Manager.

The top of the work area displays two sets of filters. Based on the user's filter selection, the table is populated with source and target volumes. Nicknames are created by the user when resources are created and are used as part of an overall scheme or naming convention for making resources easier to identify and manage.

Menu path

Fields

Storage complex

The nicknames of storage complexes that are available for selection. This list includes any 2107 and 1750 storage complexes and 2105 Copy Services domains that have been added using the Storage complex main page. A storage complex describes a group of storage units such as the DS6000™s that are managed by a single management console. If you have only one DS6000 storage unit, your storage complex consists of one storage unit. The default value for this field is "None selected".

Storage unit

The nicknames of storage units that are available for selection. This list includes any nickname that is associated with any 2107, 1750 and 2105 Model 800 that is currently displayed on the Storage units main page. The default value for this field is "None selected".

Resource type

The type of resource (LSS, Host, Volume group, Show All Volumes) from which to select volumes. The value of the selection in this field determines the field that is displayed to the right of this field. The default value for Resource type is LSS. The following resource type values and the respective field names are displayed:

• For LSS: Specify LSS
• For Host: Specify Host attachment
• For Volume Group: Specify Volume group
• For Show All Volumes: Specify Storage type

Specify LSS

The list of LSS identifiers that are available for selection. An LSS is a group of up to 256 logical volumes that have the same disk format, either count key data (CKD) for zSeries environments or fixed block (FB) for open-system environments. The default value for this field is "None selected".

Specify Host attachment

The list of host attachment identifiers that are available for selection. A host attachment identifier specifies the host type, attachment port type (either FC Switch fabric (P-P) or FC Arbitrated loop) and worldwide port name (WWPN) of a host port. The default value for this field is "None selected".

Specify Volume group

The list of volume groups that are available for selection. A volume group, specified as a nickname, is a collection of logical volumes. The default value for this field is "None selected".

Show All volumes

The list of volume types that are available for selection. The entries in the list are "None selected", "All FB Volumes", and "All CKD Volumes". If "None selected" is selected, the table is empty. For the zSeries^® environments, the data that is stored in a storage unit is arranged in a count-key-data (CKD) format. For the open system environments, the data that is stored in the storage unit is arranged in a fixed-block (FB) format. The default value for this field is "None selected".

Select

The check boxes for selecting items in the table on which to perform actions. The default value for this field is not selected.

Source Nickname

The nickname of the source volume. If you click on the link for a particular source nickname in the table, the FlashCopy properties — General page is displayed for that FlashCopy relationship. If a FlashCopy relationship does not exist, the table is empty.

Source Number

The volume number (or name, such as 1E3B) of the source volume. The volume number is a 4-digit hexadecimal value that consists of the logical subsystem (LSS) number and the volume device number, LLVV, where LL is the LSS number and VV is the volume device number.

Target Nickname

The nickname of the target volume.

Target Number

The volume number (or name, such as 1E2C) of the target volume. The volume number is a 4-digit hexadecimal value that consists of the logical subsystem (LSS) number and the volume device number, LLVV, where LL is the LSS number and VV is the volume device number.

Status

The status of the FlashCopy relationship displays one of the following:

• Copy complete (A background copy has initiated and has completed.)
• Background copy initiated (A background copy has initiated and has not completed.)
• Out of synch tracks >0 (A background copy has not been initiated).

Persistent

Displays whether the FlashCopy relationship between the volume pair is persistent (Yes or No). For persistent FlashCopy relationships, the relationship between the source and target volumes remains after a background copy completes and continues until you delete it. Creating a persistent FlashCopy relationship prevents another FlashCopy task from writing to the target volume before you have explicitly withdrawn the FlashCopy relationship. This option is a prerequisite for using the Refresh target volume operation to incrementally resynchronize the FlashCopy relationship, and is automatically selected when you select the Enable change recording option.

Change Recording

Displays whether the FlashCopy Change recording feature is Enabled or Disabled on the volume pair. When the Change recording feature is enabled, the storage unit keeps track of updates to both the source and target volumes from the time that you create the FlashCopy relationship. When change recording is enabled on a FlashCopy volume pair, the persistent option is automatically enabled on the same volume pair as well because both are required when you want to use the Refresh target volume operation later to incrementally resynchronize the FlashCopy relationship. The Refresh target volume operation makes the target volume current with the newly established point in time source copy efficiently because only changed tracks must be copied.

Restorable

Displays whether the FlashCopy relationship is restorable (Yes or No). This feature is relevant only to FlashCopy consistency group operations within a Global Mirror configuration. If the FlashCopy relationship is restorable, changes to the FlashCopy target volumes can be discarded or committed to recover from a failure during the formation of a FlashCopy consistency group.

Sequence number

Displays the sequence number that is defined for the specified FlashCopy relationship when it is created. The sequence number corresponds to a particular FlashCopy relationship and is a maximum of 8 hexadecimal digits in length.

Actions

Create...

This action is always available on this page. When you select Create..., the Create FlashCopy -> Define relationship type page displays in the work area. This page is the first page of the Create FlashCopy wizard.

FlashCopy Revertible

This action is available when you select a FlashCopy relationship in the table and the relationship that you have selected has a Restorable value of No. When you select FlashCopy Revertible, the FlashCopy Revertible-> Select Common Options page is displayed in the work area. This page is the first page of the FlashCopy Revertible wizard. This action saves the target volume data to memory for disaster recovery purposes before the FlashCopy starts.

Delete

This action is available when you select one or more FlashCopy relationships in the table. When you select Delete, a confirmation warning message displays. If you click OK on the message, you delete the selected FlashCopy relationship.

Initiate Background Copy

This action is available when you select one or more FlashCopy relationships in the table. When you select Initiate Background Copy, the Initiate background copy page is displayed. When Initiate background copy is selected on a source volume that has more than one target volume, these relationships are listed on the Initiate background copy page.

Resync Target

This action is available when you select a FlashCopy relationship in the table and the relationship you have selected has a Persistent value of Yes and a Change Recording value of Enabled. If you do not enable the Persistent and Change Recording options when you create a FlashCopy relationship, you cannot perform the Resync Target action on that relationship later. When you select Resync Target, the Resync FlashCopy page is displayed. This action copies only changed data from the source to the target volume.

Reverse FlashCopy

This action is available when you select a FlashCopy relationship in the table and the relationship you have selected has a Persistent value of Yes and a Change Recording value of Enabled. If you do not enable the Persistent and Change Recording options when you create a FlashCopy relationship, you cannot perform the Reverse FlashCopy action on that relationship later. When you select Reverse FlashCopy, the Reverse FlashCopy page is displayed. This action changes the direction of the FlashCopy such that the original source volume is now the target, and the original target volume is now the source of the FlashCopy relationship.

Discard Changes

This action is available when you select a FlashCopy relationship in the table and the relationship that you have selected has a Restorable value of Yes. You might use this action only after the operation to form a FlashCopy consistency group has failed. When you select Discard Changes, the Discard Changes page is displayed. This action removes changes to the target volume that might have occurred during the failed operation to form a consistency group and resets the Restorable value to No. FlashCopy relationships that are not persistent are deleted upon confirmation of this action.

Commit Changes

This action is available when you select a FlashCopy relationship in the table and the relationship you have selected has a Restorable value of Yes. You might use this action only after the operation to form a FlashCopy consistency group has failed. When you select Commit Changes, the Commit Changes page displays. This action retains changes to the target volume that might have occurred during the failed operation to form a consistency group, and resets the Restorable value to No. FlashCopy relationships that are not persistent will be deleted upon confirmation of this action.

Properties

This action is available when you select a FlashCopy relationship in the table. When you select Properties, the FlashCopy Properties page displays with the General tab defaulted. This action displays attributes of the FlashCopy relationship and their corresponding values. The Out-of-sync tracks tab on the FlashCopy Properties page displays the source and target volume nickname and ID, and the number of tracks that have not been copied to the target volume.