Planning for logical partitions

You can create logical partitions to distribute resources within a single server and make it function as if it were two or more independent servers. Before you create logical partitions, you must assess your current and future needs. You can then use this information to determine the hardware configuration that will meet your current needs and serve as a base for meeting your future needs.

Planning for logical partitions is a multi step process. The following tasks are recommended for planning for logical partitions.

   
__ Assess your needs

Compile a list of the questions that you must answer before you create logical partition on an existing system or place your order for new hardware. The following is the list of questions:

  • What are your existing workloads? How many resources do these workloads currently require (during typical usage and at peak usage)?
  • What are your future needs? How will your existing workloads grow over the life of your system? How many new workloads do you have to support over the life of your system?
  • Do you have an existing system onto which you can consolidate the workloads? Must you upgrade the existing system before you consolidate the workloads? Does it make more sense to purchase a new system for these workloads?
  • What physical infrastructure will you have to support any new hardware? Can your current location accommodate the new hardware? Must you upgrade your power infrastructure or your cooling infrastructure?
  • Will your new hardware work with your existing hardware?
  • Which hardware features will you use? For example, do you want to use virtual I/O to consolidate I/O resources? Must you obtain activation codes or enablement codes to use these features?
  • Must you obtain more licenses to run your applications? If so, how many more licenses do you need?
  • Does the support strategy for your new hardware differ from the support strategy for your existing hardware? If so, what changes must you make to maximize the effectiveness of the new support strategy?
  • Must you migrate your workloads onto new hardware? If so, what must you do to migrate these workloads?
__ Learn about your system and its features

Your system has many features that allow you to use system resources more efficiently and simplify daily tasks. For more information about what these features are and how these features work, see Logical partition overview.

__ Learn about planning tools

IBM® provides the following tools that you can use to assess your needs, determine the hardware that you need to accommodate existing and future needs, and compile an order for the hardware that you need:

IBM Prerequisite website
The IBM Prerequisite website provides you with compatibility information for hardware features. This site helps you plan a successful system upgrade by providing you with the prerequisite information for features that you currently have or plan to add to your system.
IBM Systems Workload Estimator
The IBM Systems Workload Estimator (WLE) estimates the computer resources that are required for Domino®, WebSphere® Commerce, WebSphere, Web Serving, and traditional workloads. The WLE projects the most current server models that meet the capacity requirements that are within the CPU percent utilization objectives.
AIX® Performance Toolbox for POWER®
The AIX Performance Toolbox (PTX) for POWER is a licensed program that provides a comprehensive tool for monitoring and tuning system performance in distributed environments.
__ Take inventory of your current environment

Monitor resource usage on your existing servers to determine the amounts of resources that you currently use in your operation. You will use this information as a basis for determining the resources that you require on the consolidated system. The Performance Monitor (PM) information that you gather from your existing systems gives you the information that you need to analyze existing workloads.

__ Perform capacity planning

Analyze the workloads that are to be consolidated onto your managed system and determine the amounts of resources that these workloads require. You will also want to calculate the resources that you will need for future growth and determine whether your hardware can accommodate this growth. To analyze your current workloads, use your PM information as input for the WLE. The WLE uses this input to determine the resources that you need for the consolidated workloads. The WLE also allows you to project how many resources you will need in the future.

__ Decide which tool you want to use to create logical partitions and manage the system

Determine whether you want to use the Hardware Management Console (HMC), or the Virtual Partition Manager to create logical partitions and manage the system. To learn about these tools, see Logical partitioning tools.

__ Decide if you want your operating systems to share I/O resources with each other

Determine whether you want to set your logical partitions to use virtual I/O resources from a Virtual I/O Server logical partition. For more information, see Virtual I/O Server.

__ Design and validate your logical partition configuration

Design the logical partitions that you will create on the managed system, and assign resources to each logical partition so that the logical partitions can perform their assigned tasks efficiently.

__ Design network infrastructure to connect logical partitions with each other and with external networks

Determine what types of physical and virtual adapters you want to use to connect logical partitions to each other and to external networks. For more information about the different methods that you can use to connect logical partitions with each other and with external networks, see I/O devices.

__ Identify how the managed system communicates with the HMC

Determine how you want to connect your managed system and its logical partitions with the HMC that manages the system. For more information about the ways in which you can connect your managed system with the HMC, see HMC network connections.

__ Determine a service and support strategy

Determine how to apply fixes to your server and identify problems that need to be reported to your service provider. The HMC can be configured to report most problems to your service provider automatically. For more information about how to set up the HMC to report problems, see Configuring the local console to report errors to service and support.

__ Plan for software licensing in a partitioned environment

Determine the number of software licenses that you need for your logical partition configuration. For instructions, see Software licensing for IBM licensed programs on logical partitions.