IPL
Initial program load: starting z/OS on a system, the mainframe word for booting.
Also written initial program load, re-IPL, IPL the system
IPL stands for initial program load. It is how z/OS is started on a system, and it is the mainframe word for what other computers call booting. People say "we IPL on Sunday" or "that change needs an IPL".
An operator starts the IPL from the hardware console. They name the disk volume that holds the operating system, and a load parameter that tells z/OS which set of start-up settings to use. z/OS then reads its configuration, mostly from members of a library called PARMLIB, and starts its own components and subsystems.
IPLs are rare and planned. A z/OS system often runs for weeks or months between them. Many changes can be made while the system is running, so an IPL is usually saved for maintenance that cannot be applied any other way.
In a sysplex, one system can be IPLed while the others keep running the work, so users may not notice. If you hear that a system "was IPLed", it simply means it was stopped and started again.
Where can I learn this hands-on?
Right here, at ZedBank. You take a junior job at a simulated bank and learn each part of the work by doing it, with Zed beside you. There's nothing to install.
Start at ZedBankRelated
- z/OSThe main operating system that runs on IBM mainframes, in the same way Windows or Linux runs on a laptop or server.
- LPARA logical partition: one physical mainframe carved into several independent virtual machines, each running its own operating system.
- OperatorThe person who watches the running systems, responds to messages, and starts, stops and recovers work.
- System programmerThe person who installs, configures, tunes and upgrades the operating system and its subsystems.
- PARMLIBThe library of members that holds z/OS's own settings, read when the system starts and on some commands.
- SysplexA group of mainframe systems joined together so they behave as one, sharing work and data so that no single failure stops the service.