When you select "A single source with a single target" on the Define
relationship type page to create one-to-one FlashCopy® relationships, you must
select the same number of target volumes as you selected source volumes. Use
this page to select target volumes to participate in a one-to-one FlashCopy relationship.
Introduction
After
you select source volumes, use this page to select target volumes to participate
in a one-to-one FlashCopy relationship.
Consider the following guidelines when you select target volumes:
- The size of the target volume must be at least as large as the source
volume that you selected. If you plan to reverse the direction of the FlashCopy relationship,
the size of the source and target volumes must be identical. When the current
target volume becomes the new source volume, the new target (the current source)
volume must be at least as large as the new source.
- The source and target volume for FlashCopy must reside in the same
storage unit; however, the source and target volumes can be in different LSSs.
- The storage type (fixed block [FB] or count key data [CKD] format) of
the volumes that you select as a target volume must match the storage type
of the source volume. For example, if the source volume is FB format, you
must select only an FB format volume as the target volume for that source
volume. If the source volume is CKD format, you must select only a CKD format
volume as the target volume for that source volume.
- Volumes that are already defined to another FlashCopy relationship are not eligible
for selection and are not displayed.
- If you have selected more than one FlashCopy source volume, the FlashCopy target
volumes that you select are associated with source volumes sequentially by
volume ID such that the lowest source volume ID will be paired with the lowest
target volume ID, the next highest source volume ID will be paired with the
next highest target volume ID, and so on.
Menu path
Fields
- Resource type
- The type of resource from which to select target volumes. You must select
one type of resource from the drop-down menu. The type of resource that defaults
corresponds to the selection that you made on the Select source volumes page.
The following values are available for type of resource:
- LSS: The logical subsystem identifier. An LSS is a group of logical volumes
that have the same disk format, either count key data (CKD) for zSeries environments
or fixed block (FB) for open-system environments. There is a one-to-one mapping
between a CKD logical subsystem and a zSeries control-unit image. For zSeries
hosts, a logical subsystem represents a logical control unit (LCU). Each control-unit
image is associated with only one logical subsystem.
- Host attachment: A host attachment identifier that 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.
- Volume group: a collection of logical volumes that is specified as a nickname.
- Show All volumes: All volumes that are eligible to be selected as target
volumes for the selected source volume.
- The value in this field determines the Specify field that is displayed
to the right of this field. 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".
- Specify Storage Type
- 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 target volumes in the table. The default
value for this field is not selected.
- Nickname
- The nickname of the volume. If there are no volumes that meet the selection
criteria that you specified, the table is empty.
- Volume Number
- The volume number (also called the Volume
ID). 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.
- GB(2^30)
- The size, in binary gigabytes, of the volume. One binary GB (2^30) = 1 073 741 824
bytes. Volumes of Type DS are configured in binary format. This method provides
volumes that fully use the capacity in every extent.
- GB(10^9)
- The size, in decimal gigabytes, of the volume. One decimal GB (10^9)
= 1 000 000 000 bytes. ESS 2105 volumes are configured in decimal format.
- Extent Pool
- The nickname of the extent pool to which the volume is assigned.
Note: An
extent pool is a grouping of extents. An extent is a contiguous set of allocated
tracks and consists of a beginning track, an end track, and all tracks in
between. Extent size can range from a single track to an entire volume.
- Host Attachments
- The number of host attachments (interfaces) that are used to connect open-systems
hosts to the volume. The value in this field is a hyperlink to the Host systems
main page.
- < Back
- Takes you to the previous step of the wizard.
- The previous step of the Create FlashCopy wizard is Select source
volumes.
- Next >
- Takes you to the next step of the wizard. You cannot proceed to the next
step until you have completed all required fields.
- The next step of the Create FlashCopy wizard is Select common
options.
- Finish
- Completes the task and takes you to the main page. This button is disabled
until you enter all of the required information in the wizard.
- This button is disabled because this is not the last step of the Create FlashCopy wizard.
- Cancel
- Ends the wizard and returns you to the main page without completing the
task.
- If you click the Cancel button, the FlashCopy main page is displayed.