12 Experiences with Oracle for Linux on zSeries
2.1 Deployment options
The major decisions to be made when deploying Linux/390 are:
Should the Linux machine images be guests under z/VM, or should they be
run natively in a logical partition provided by the Processor
Resource/Systems Manager (PR/SM) feature available on zSeries
Should the Linux images be run on the zSeries processor general purpose
CPs, or using IFL CPs?
Should we use the SuSE or Red Hat distribution of Linux?
What network topology should we use to connect the Linux machine images
to the network?
How much CPU and memory resource should be allocated to the Linux
2.1.1 z/VM or LPAR?
zSeries processors have a feature called Processor Resource/Systems Manager
(PR/SM) which allows the z/800 or z/900 processor to run in Logical Partitioned
(LPAR) mode. In this mode, the zSeries processor can be divided up into up to
15 logical partitions (LPs). Each of these LPs can run a separate operating
system, such as z/OS, z/VM or Linux. The PR/SM feature isolates the different
LPs so they run completely independent from one another.
z/VM is an operating system that provides support for multiple
each with their own operating system. The virtualization capability of z/VM allows
you to run an effectively unlimited number of operating system images on the
same z/900 or z/800 machine. By providing virtual machine facilities, z/VM also
simplifies the management of multiple guest operating systems. See
GC24-5991 for more information on z/VM. The redbook
Large Scale Linux Deployment,
SG24-6824 also has a chapter that provides a
basic introduction to z/VM.
Deploying in a logical partition
LPAR mode supports a maximum of 15 logical partitions. Each of these LPs can
run a different operating system. Many customers will already run their zSeries
processor in LPAR mode to support z/OS or OS/390 images for their normal
work. It is not that difficult to add another logical partition to run Linux.