IPL type
The IPL type determines which copy of programs your system uses during the initial program load (IPL).
There are four IPL types:
- IPL type A
- Use IPL type A when directed for special work, such as applying fixes
(PTFs) and diagnostic work. For example, use IPL type A in the following circumstances:
- When IPL type B fails
- When the procedures direct you to use IPL type A
- When you suspect problems with temporary Licensed Internal Code fixes.
IPL type A uses the A copy of Licensed Internal Code during and after the IPL. This copy of Licensed Internal Code is the permanent copy. It resides in System Storage Area A. It contains no temporarily applied fixes.
- IPL type B
- Use IPL type B for routine work and when directed by a PTF procedure.
This type of IPL runs the newest copy of Licensed Internal Code and is necessary
when you permanently apply certain fixes.
IPL type B uses the B copy of Licensed Internal Code during and after the IPL. This copy resides in System Storage Area B. This copy contains temporarily applied fixes.
- IPL type C
- Rochester development support reserves this type of IPL for hardware service
representatives.Attention: Do not use this function. Data loss can occur with improper use of this function.
- IPL type D
- Use IPL type D when directed for special work, such as installing and
reloading programs.
IPL type D loads the system programs from an alternate IPL load source, such as a tape drive or CD-ROM.
Typically an IPL uses programs that are stored on the primary IPL load source (typically a disk drive). Sometimes it is necessary to perform an IPL from another source, such as programs that are stored on tape. To do this, you must use IPL type D to perform an IPL from the alternate IPL load source.
Use IPL type D only during one of the following situations:
- When the installation or restore procedures direct you to use IPL type D
- When IPL type B and IPL type A fail (when the primary IPL load source cannot perform an IPL on the system properly) and only when directed by your support personnel
- When service directs you to perform an alternate installation