Creating count key data volumes using the DS CLI

Complete this task to create count key data (CKD) volumes.

A logical volume consists of one or more data extents that are allocated from a single extent pool. The volume data type is inherited from the extent pool extent storage type (fixed block or CKD) characteristic. When a CKD volume is created, volume attributes are further defined by a base or alias volume type, 3390 or 3380 volume cylinder type, and volume capacity in cylinders. These volume attributes characterize the volume to the host system that will eventually access the volume. Each volume is assigned a volume ID, which is the volume address within the 64 KB address space. Host access to a volume is enabled when the volume ID is assigned to a volume group; however, CKD volumes are automatically assigned to the volume group CKD FICON/ESCON All (ID V10).

Perform the following steps to create your CKD volumes:

View your list of CKD extent pool IDs and determine which extent pool IDs that you want to use as the source for the CKD volumes to be created. You obtained this list when you first created your extent pools. If this list is not available, you can issue the lsextpool command to obtain the list of extent pool IDs.
Extent pool attributes determine the size and quantity of volumes that can be created. The extent pool ID (even/odd) indicates the storage server (0|1), which dictates that the logical control unit (LCU) ID component of the volume ID must be an even or an odd number.
Issue the mkckdvol command to make 128 base volumes for each LCU. Enter the mkckdvol command at the dscli command prompt with the following parameters and variables:
```
dscli>mkckdvol –dev IBM.1750-68FA120 -extpool p1 –cap 3339
 –name finance#d 0000-007F
```
The following considerations affect the command example in this step:
- The -extpool parameter identifies a CKD extent pool that contains available data extents.
- The -cap parameter specifies the quantity of CKD cylinders that are allocated to this volume.
- The -name parameter allows you to assign an easy-to-use label or nickname to the volume. The volume name parameter can include a wild card (#d or #h) that inserts a decimal or hexadecimal volume ID value into the volume name.
  Note: The decimal designation does not apply to the volume ID number or the number of volumes that were created by the command. It only applies to the unique name that you have assigned to the volume. When you process the mkckdvol command, the volume name that you have assigned does not appear in the confirmation message. To view the volume name that you have assigned, issue the lsckdvol or showckdvol command.
- Volume ID 0000 - 007F specifies 128 volumes, starting at CKD address group (0), LCU ID (00), and volume number (00). You must specify volume IDs that have not been previously defined as CKD or fixed block volumes.
Press Enter to create the volumes. A confirmation message is displayed that lists the successful creation of each volume.
Repeat Steps 2 and 3 until all required logical volumes for all LCUs have been created.
Issue the mkaliasvol command to make 128 alias volumes for each LCU. Enter the mkaliasvol command at the dscli command prompt with the following parameters and variables:
```
dscli>mkaliasvol –dev IBM.1750-68FA120 –base 0000-004F
 -order decrement -qty 2 00FF
```
Consider the following conditions with regard to the command example in this step:
- The -base 0000 - 004F parameter specifies that alias volumes are assigned to existing base volume IDs 0000 - 004F. Base and alias volumes must be associated with a common LCU ID.
- The -order parameter specifies the order in which alias volume IDs are assigned.
- The -qty parameter specifies the number of alias volumes that are assigned to each base volume.
- The volume ID (00FF) parameter specifies that the alias volumes are assigned, starting at a CKD address group (0), LCU ID (00) and volume number (FF). You are responsible for specifying the volume ID values that have not been previously defined as CKD or fixed block volume types.
  As a result, alias volumes 00FF and 00FE are created for base volume 0000, 00FD and 00FC for 0001, and so on.
Repeat Step 5 until you have defined all required logical volumes for all the LCUs.
Press Enter to create the alias volumes. A confirmation message is displayed that lists the successful creation of each volume.
Issue the lsckdvol command to display a report that you can use to confirm the status of your CKD volumes. Enter the lsckdvol command at the dscli command prompt with the following parameters and variables:
```
dscli>lsckdvol -dev IBM.1750-6800861 -l 1410
```
Note: It is possible that the report will display that there was a configuration error that is associated with one or more of your mkckdvol transactions. In the majority of instances, the only way to correct this error is to issue the rmckdvol command.