
Chapter 3. Logical configuration planning 63
3.5.2 Mixing open and zSeries logical disks
Open systems data is fixed block (FB) and zSeries data is count-key-data (CKD) and they are
physically different representations within the DS6000. The two data types are not able to be
mixed within an Array.
CKD
In count-key-data (CKD) organization, the data field stores the user data. Also, because the
data records can be variable in length, they all have an associated
count field that indicates
the user data record size. Then the
key field is used to enable a hardware search based on a
key. However, this is not generally used for most data anymore. Exten ...