Planning for Installation on IBM System z

13.1. Pre-installation

Red Hat Enterprise Linux 7 runs on zEnterprise 196 or later IBM mainframe systems.

The installation process assumes that you are familiar with the IBM System z and can set up logical partitions (LPARs) and z/VM guest virtual machines. For additional information on System z, see http://www.ibm.com/systems/z.

For installation of Red Hat Enterprise Linux on System z, Red Hat supports DASD (Direct Access Storage Device) and FCP (Fiber Channel Protocol) storage devices.

Before you install Red Hat Enterprise Linux, you must decide on the following:

Decide whether you want to run the operating system on an LPAR or as a z/VM guest operating system.

Decide if you need swap space and if so, how much. Although it is possible (and recommended) to assign enough memory to a z/VM guest virtual machine and let z/VM do the necessary swapping, there are cases where the amount of required RAM is hard to predict. Such instances should be examined on a case-by-case basis. See Section 15.10.3.5, “Recommended Partitioning Scheme”.

Decide on a network configuration. Red Hat Enterprise Linux 7 for IBM System z supports the following network devices:

Real and virtual Open Systems Adapter (OSA) Real and virtual HiperSockets

LAN channel station (LCS) for real OSA You require the following hardware:

Disk space. Calculate how much disk space you need and allocate sufficient disk space on DASDs ⁠ or SCSI ⁠ disks. You require at least 2 GB for a server installation, and 5 GB if you want to install all packages. You also require disk space for any application data. After the installation, more DASD or SCSI disk partitions may be added or deleted as necessary.

The disk space used by the newly installed Red Hat Enterprise Linux system (the Linux instance) must be separate from the disk space used by other operating systems you may have installed on your system.

For more information about disks and partition configuration, see Section 15.10.3.5, “Recommended Partitioning Scheme”.

RAM. Acquire 1 GB (recommended) for the Linux instance. With some tuning, an instance might run with as little as 512 MB RAM.

13.2. Overview of the System z Installation Procedure

You can install Red Hat Enterprise Linux on System z interactively or in unattended mode. Installation on System z differs from installation on other architectures in that it is typically performed over a network and not from a local media. The installation consists of two phases:

[2]

[3]

1. Booting the Installation

Connect with the mainframe, then perform an initial program load (IPL), or boot, from the medium containing the installation program. See Chapter 14, Booting the Installation on IBM System z for details.

2. Anaconda

Use the Anaconda installation program to configure network, specify language support, installation source, software packages to be installed, and to perform the rest of the installation. See

Chapter 15, Installing Red Hat Enterprise Linux on IBM System z for more information.

13.2.1. Booting the Installation

After establishing a connection with the mainframe, you need to perform an initial program load (IPL), or boot, from the medium containing the installation program. This document describes the most common methods of installing Red Hat Enterprise Linux on System z. In general, you can use any method to boot the Linux installation system, which consists of a kernel (kernel.im g) and initial RAM disk

(initrd.im g) with at least the parameters in the generic.prm file. The Linux installation system is also called the installation program in this book.

The control point from where you can start the IPL process depends on the environment where your Linux is to run. If your Linux is to run as a z/VM guest operating system, the control point is the control program (CP) of the hosting z/VM. If your Linux is to run in LPAR mode, the control point is the mainframe's Support Element (SE) or an attached IBM System z Hardware Management Console (HMC).

You can use the following boot media only if Linux is to run as a guest operating system under z/VM:

z/VM reader – see Section 14.3.1, “Using the z/VM Reader” for details.

You can use the following boot media only if Linux is to run in LPAR mode:

SE or HMC through a remote FTP server – see Section 14.4.1, “Using an FTP Server” for details.

SE or HMC DVD – see Section 14.4.4, “Using an FCP-attached SCSI DVD Drive” for details.

You can use the following boot media for both z/VM and LPAR:

DASD – see Section 14.3.2, “Using a Prepared DASD” for z/VM or Section 14.4.2, “Using a Prepared DASD” for LPAR.

SCSI device that is attached through an FCP channel – see Section 14.3.3, “Using a Prepared FCP-attached SCSI Disk” for z/VM or Section 14.4.3, “Using a Prepared FCP-FCP-attached SCSI Disk” for LPAR.

FCP-attached SCSI DVD – see Section 14.3.4, “Using an FCP-attached SCSI DVD Drive” for z/VM or Section 14.4.4, “Using an FCP-attached SCSI DVD Drive” for LPAR

If you use DASD and FCP-attached SCSI devices (except SCSI DVDs) as boot media, you must have a configured zipl boot loader.

13.2.2. Installation using Anaconda

In the second installation phase, you will use the Anaconda installation program in graphical, text-based, or command-line mode:

Graphical Mode

Graphical installation is done through a VNC client. You can use your mouse and keyboard to navigate through the screens, click buttons, and type into text fields. For more information on performing a graphical installation using VNC, see Chapter 22, Installing Using VNC.

Text-based Mode

This interface does not offer all interface elements of the GUI and does not support all settings.

Use this for interactive installations if you cannot use a VNC client. For more information about text-based installations, see Section 15.1.3, “Installation in Text Mode”.

Command-line Mode

This is intended for automated and non-interactive installations on System z. Note that if the installation program encounters an invalid of missing kickstart command, the system will reboot.

For more information about automated installation, see Chapter 23, Kickstart Installations.

In Red Hat Enterprise Linux 7 the text-based installation has been reduced to minimize user interaction.

Features like installation on FCP-attached SCSI devices, customizing partition layout, or package add-on selection are only available with the graphical user interface installation. Use the graphical installation whenever possible. See Chapter 15, Installing Red Hat Enterprise Linux on IBM System z for more details.

[2] Direct Access Storage Devices (DASDs) are hard d isks that allo w a maximum o f three p artitio ns p er d evice. Fo r examp le, dasda can have p artitio ns dasda1, dasda2, and dasda3.

[3] Using the SCSI-o ver-Fib re Channel d evice d river (the zfcp d evice d river) and a switch, SCSI LUNs can b e p resented to Linux o n System z as if they were lo cally attached SCSI d rives.