Access to FICON and FCP disk storage through storage groups

Administrators use the Configure Storage task to configure access to Fibre Connection (FICON®) extended count key data (ECKD) direct-access storage devices (DASD), and Fibre Channel Protocol (FCP) Small Computer System Interface (SCSI) disk storage devices.

After the initial storage configuration is complete and the system is connected to physical storage hardware by cables, system administrators can enable partitions to access and use those resources by creating storage groups. A storage group is a logical group of storage volumes that share certain attributes. One attribute is the type; another is shareability, which indicates whether the storage group is defined as either dedicated for use by only one partition, or shared by multiple partitions.

To create a storage group, open the Configure Storage task and select one of the following options: REQUEST STORAGE or CREATE STORAGE GROUP. (The option that you can select depends on the authorization of your user ID.) Using this task does not require extensive knowledge of mainframes or LinuxONE systems; however, a storage administrator must fulfill any requests for storage. You can create one or more storage groups through a single request by defining one storage group and specifying the number of duplicates.

When you submit a request for one or more storage groups, DPM automatically generates the world wide port names (WWPNs) that are allocated to virtual storage resources when the storage group is attached to a partition. Also, DPM automatically generates a request that you can send as email to one or more storage administrators to fulfill through the storage subsystem management interface.

To access storage, attach one or more storage groups to a partition, through either the New Partition task or Partition Details task. Figure 1 shows several storage groups with key attributes, and information about the physical devices that an administrator has configured to fulfill them.

Figure 1. Sample FICON and FCP storage groups that are attached to partitions on the system
This diagram illustrates key characteristics of storage groups, which are attached to partitions
In Figure 1, the ovals in the partitions indicate which storage groups are attached to each partition.
  • Partition A can access storage group SG01, which consists of a set of FICON base volumes that are dedicated for use by only one partition. Partition A accesses these volumes through FICON-mode adapter card 01 and switch A.
  • Partitions A and B share storage group SG02, which consists of FCP disks that both partitions can access through FCP-mode adapter card 22 and switch B.
  • Similarly, partitions B and C share storage group SG03, which consists of FCP disks that both partitions can access through FCP-mode adapter card 31 and cascaded switches B and C.