Configuring the Linux operating system for IBM z Systems® hosts

You must configure the Linux® operating system before you can use z Systems® hosts with the system.

Multipath support for IBM z Systems hosts

You must install multipathing software on all z Systems hosts that are attached to the system.

On z Systems hosts that are running the Linux operating system, the following software provides multipathing support:
Linux Kernel 2.4
The logical volume manager.
Linux Kernel 2.6
  • The multipath-tools package on SUSE Linux Enterprise Server.
  • The device-mapper-multipath package on Red Hat Enterprise Linux.

For more information about using the logical volume manager or the multipathing tools package with z Systems hosts that run Linux kernel 2.4 or Linux kernel 2.6, see the documentation at the following website:

www.ibm.com/developerworks/linux/linux390/index.html.

Installing and configuring the host bus adapter on an IBM Z® host system

The host bus adapters (HBAs) for an IBM Z® host system must be ordered as features. These features are either factory-installed when you order a new system or installed into an existing system by a service representative.

To configure the HBA:
  • Ensure that the appropriate features (FICON®, FICON Express, FICON Express2, or FICON Express4) are installed on your IBM Z® host system.
  • Configure the HBA to run in FCP mode.

For more information about FCP connectivity, see www.ibm.com/support.

SAN boot support on IBM z Systems hosts

On a SCSI LUN, you can complete an initial program load (IPL) process.

IPL processes on SCSI LUNs can fail because there is no path failover capability during the boot process. See the latest How to use FC-attached SCSI devices with Linux on z Systems publication for more information about using IPL processes with z Systems hosts.

Defining the number of disks on IBM z Systems hosts

When you define the number of disks on z Systems hosts that are running the Linux operating system, you are provisioning capacity for configured disks.

On the Linux operating system, a device node is used for each path to the disk and a second device node is used for the path grouped device. The maximum number of devices depends on your Linux configuration.

System configuration for IBM z Systems hosts

Each attached system LUN has a set of device files in the /dev Linux directory.

These device files are intended to be used only by the multipath tools. Allowing them to be used directly by your system or applications can produce data inconsistencies. Instead, configure your system and applications to use the device nodes that are created by the multipath tools.