IBM DS6000 Series Positioning the IBM TotalStorage DS6000 series, Simplified LUN masking, Summary

On an ESS there was a predefined association of arrays to Logical Subsystems. This caused some inconveniences, particularly for zSeries customers. Since in zSeries one works with relatively small volume sizes, the available address range for an LSS often was not sufficient to address the whole capacity available in the arrays associated with the LSS. On the other hand, in large capacity configurations where large CKD volumes were used, clients had to define several address ranges, even when there were only a few addresses used in an LSS. Several customers were confronted with a zSeries addressing limit of 64K addresses.

There is no predefined association of arrays to LSSs on the DS6000 series. Clients are free to put LUNs or CKD volumes into LSSs and make best use of the 256 address range of an LSS.

Simplified LUN masking

The access to LUNs by host systems is controlled via volume groups. Hosts or disks in the same volume group share access to data. This is a new form of LUN masking. Instead of doing LUN masking for individual World Wide Port Names (WWPN), as implemented on the ESS, you can now do LUN masking at the host level by grouping all or some WWPNs of a host into a so-called Host Attachment and associating the Host Attachment to a Volume Group.

This new LUN masking process simplifies storage management because you no longer have to deal with individual Host Bus Adapters (HBAs) and volumes, but instead with groups.

Summary

In summary, the DS6000 series allows for:

￿Up to 32 logical subsystems

￿Up to 8192 logical volumes

￿Up to 1040 volume groups

￿Up to 2 TB LUNs

￿Large z/OS volumes with up to 65520 Cylinders

1.3Positioning the IBM TotalStorage DS6000 series

The IBM TotalStorage DS6000 series is designed to provide exceptional performance, scalability, and flexibility while supporting 24 x 7 business operations to help provide the access and protection demanded by today's business environments. It is also designed to deliver the flexibility and centralized management needed to lower long-term costs. It is part of a complete set of disk storage products that are all part of the IBM TotalStorage DS Family and it is the disk product of choice for environments that require the highest levels of reliability, scalability, and performance available from IBM for mission-critical workloads. Clients who currently have IBM TotalStorage ESS models in their enterprise should also consider the IBM TotalStorage DS6000 series when they plan to replace or buy additional storage.

The IBM TotalStorage DS6000 series is designed for the cost, performance, and high capacity requirements of today's on demand business environments.

The DS6000 series is ideally suited for storage consolidation because it offers extensive connectivity options. A broad range of server environments, including IBM eServer zSeries, iSeries, xSeries, BladeCenter, and pSeries servers, as well as servers from Sun, HP, and other server providers are supported. This rich support of heterogeneous environments and

Chapter 1. Introducing the IBM TotalStorage DS6000 series 15