An independent ASP is actually a part of the larger construct of an auxiliary storage pool (ASP). Each ASP on your system is a group of disk units that can be used to organize data for single-level storage to limit storage device failure and recovery time. The system spreads data across the disk units within an ASP.
Figure 32 shows the types and subtypes of ASPs. The system ASP (ASP 1) is defined by the system and consists of disk unit 1 and any other configured storage not assigned to a basic or independent ASP. The system ASP contains the system objects for the operating system and any user objects not defined to a basic or independent ASP.
User ASPs are additional ASPs defined by the user. A user ASP can either be a basic ASP or an independent ASP.
One type of user ASP is the basic ASP. Data that resides in a basic ASP is always accessible whenever the server is running. Basic ASPs are identified as ASPs 2 through 32. Attributes, such as those for spooled files, authorization, and ownership of an object, stored in a basic ASP reside in the system ASP. When storage for a basic ASP is filled, the data overflows into the system ASP.
Collectively, the system ASP and the basic ASPs are called SYSBAS.
Another type of user ASP is the independent ASP. Identified by device name and numbered 33 through 255, an independent ASP can be made available or unavailable to the server without restarting the system. Unlike basic ASPs, data in an independent ASP cannot overflow into the system ASP. Independent ASPs are configured using iSeries Navigator.
Figure 32.Types of auxiliary storage pools
Subtypes of independent ASPs consist of primary, secondary, and user-defined file system (UFDS) independent ASPs1. Subtypes can be grouped together to function as a single entity known as an ASP group. An ASP group consists of a primary independent ASP and zero or more secondary independent ASPs. For example, if you make one independent ASP unavailable, the others in the ASP group are made unavailable at the same time.
A primary independent ASP defines a collection of directories and libraries and may have associated secondary independent ASPs. A primary independent ASP defines a database for itself and other independent ASPs belonging to its ASP group. The primary independent ASP name is always the name of the ASP group in which it resides.
A secondary independent ASP defines a collection of directories and libraries and must be associated with a primary independent ASP. One common use for a secondary independent ASP is to store the journal receivers for the objects being journaled in the primary independent ASP.
Before an independent ASP is made available (varied on), all primary and secondary independent ASPs in the ASP group undergo a process similar to a server restart. While this processing occurs, the ASP group is in an active state and recovery steps are performed. The primary independent ASP is synchronized with any secondary independent ASPs in the ASP group, and journaled objects are synchronized with their associated journal.
While being varied on, several server jobs are started in the QSYSWRK subsystem to support the independent ASP. To ensure that their names remain unique on the server, server jobs that service the independent ASP are given their own job name when the independent ASP is made available.
Once the independent ASP is made available, it is ready to use. Completion message CPC2605 (vary on completed for device name) is sent to the history log.
1. MIMIX does not support UDFS independent ASPs. UDFS independent ASPs contain only user-defined file systems and cannot be a member of an ASP group unless they are converted to a primary or secondary independent ASP.