The HP Virtual Server Environment : nPartition Management Paradigms (part 1) - Local nPartition Management Paradigm

HP nPartition Servers support three management paradigms. These paradigms enable administrators to manage nPartitions in the mode which best suits their environments. The three management paradigms are as follows:

• Local Management has been the most commonly used paradigm for managing nPartitions because it was the only supported paradigm on the first-generation nPartition servers. Local management entails logging into an nPartition on the complex and executing the management tools directly on the nPartition. Using local management, an administrator has the ability to either make changes to the entire complex or limit management capabilities to those that affect only the local nPartition.

• Remote Management via an nPartition allows administrators to manage the complex from a central management station. This enables more efficient management because the administrator need not log into each nPartition to be managed and start the respective management tools. Instead, the management tools can be executed from a single location and directed toward each nPartition to be managed. In addition, only a subset of the management components needs to be running on the nPartitions.

• Remote Management via the MP enables administrators to fully configure an nPartition server without running any of the management software components on the nPartitions. In addition, this management paradigm affords similar benefits regarding remote management via an nPartition and the ability to manage many complexes from a central management station. Finally, this management paradigm provides a means to perform system administration even if no nPartition is active in the complex.

Local nPartition Management Paradigm

Figure 1 shows the paradigm of local nPartition management. This paradigm applies to all HP nPartition servers. Local nPartition management involves logging into an nPartition on the complex and performing management tasks on the local nPartition. This architecture is the simplest to use out of the box because it requires only a single system, the nPartition, to be operating in order to perform nPartition management. However, this management paradigm doesn't take full advantage of the remote management capabilities available on HP nPartition servers; this topic will be discussed in the following sections.

Figure 1. Local nPartition Management Paradigm

nPartition management applications for the original HP 9000 nPartition servers use a proprietary interface to communicate with the MP for configuration tasks. This interface enables nPartition management tools to configure the entire complex from any nPartition within the complex. nPartition management tools provide some limitations on configuration changes from one nPartition to another, such as disallowing the removal of an active nPartition from another nPartition. However, most operations are allowed from any nPartition in the complex. This provides a simplified and flexible management model, as an administrator may log into a single nPartition and perform several tasks that affect other nPartitions. The ramifications of this simplicity and flexibility should be considered when managing a shared HP nPartition server.

The second-generation HP nPartition servers, which contain the sx1000 chipset, use the Intelligent Platform Management Interface (IPMI) protocol as the interface between the MP and the management applications. IPMI is an industry-standard protocol designed to facilitate low-level system management. The IPMI interface is supported on HP-UX, Microsoft Windows, and Linux operating systems for the HP nPartition servers containing the sx1000 chipset and later chipsets. As implemented on HP nPartition servers, IPMI supports two transport mechanisms for communicating with the MP. The first is block transfer (BT) and the second is LAN. These are commonly referred to as IPMI over BT (IPMI/BT) and IPMI over LAN (IPMI/LAN). The IPMI/BT transport goes though a kernel driver on an nPartition to communicate with the MP. The IPMI/LAN transport uses the MP's LAN interface for communication.

While nPartition management has remained very similar between the generations of HP nPartition servers, several enhancements have been added. The most notable enhancement relating to Figure 1 and the use of the IPMI/BT interface is a feature called the nPartition configuration privilege. This feature can be enabled on the MP by using the PARPERM command from the MP's command menu as shown in Listing 1.

note

The nPartition configuration privilege is supported only on HP nPartition servers based on the sx1000 chipset and later chipsets. This feature is not available on the first-generation HP 9000 nPartition servers.

Listing 1. Enabling the nPartition Configuration Privilege

Welcome to the rx8620 Management Processor (c) Copyright 1995-2003 Hewlett-Packard Co., All Rights Reserved. Version A.5.011 MP MAIN MENU: CO: Consoles VFP: Virtual Front Panel (partition status) CM: Command Menu CL: Console Logs SL: Show Event Logs HE: Help X: Exit Connection MP> cm Enter HE to get a list of available commands MP:CM> parperm This command configures the nPartition Configuration Privilege. WARNING: When nPartition Configuration Privilege is unrestricted, configuration commands issued by one partition can affect the configuration of another partition. When this privilege is restricted, configuration commands issued by a partition cannot affect power or partition assignment of hardware not already assigned to the partition. Restricting nPartition configuration privilege does not restrict deallocation of processors across partition boundaries. nPartition Configuration Privilege is currently unrestricted. Do you wish to restrict partition configuration (preventing partitions from changing the configuration of the platform)? (Y/[N]) y -> Partition reconfiguration is disabled MP:CM>

When the nPartition configuration privilege is enabled (restricted), only configuration changes to the PCD data structure for the nPartition from which the request originated are allowed. Therefore, an administrator on one nPartition may not make changes to the SCCD or any other nPartition's PCD. In order to change the SCCD and the PCD data structures other than the PCD for the local nPartition, the administrator must use the IPMI over LAN interface; this is described in the next section.

In Figure 1, immediately above the IPMI or HP proprietary kernel interface component is the nPartition provider. The nPartition provider is a software component that implements the Web-Based Enterprise Management (WBEM) standard provider interface. Since an industry-standard WBEM interface for nPartition configuration is available for HP nPartition servers, third-party management tools are able to integrate with HP's nPartition servers.

Next to the nPartition provider component is the instant capacity provider. Similar to the nPartition provider, the instant capacity provider exposes an industry-standard interface for managing unlicensed components on HP nPartition servers. The nPartition management infrastructure verifies all changes to the SCCD and PCD data structures with the instant capacity provider to ensure that the complex remains in compliance with the number of unlicensed resources. All nPartition configuration changes on complexes containing unlicensed components must be made through an nPartition running HP-UX. The interface between the nPartition provider and the instant capacity provider is built to deny all configuration changes on complexes with unlicensed resources if the operating system is not HP-UX. For complexes that weren't purchased with unlicensed instant capacity components, the instant capacity provider will automatically approve all configuration changes.

Above the nPartition provider and instant capacity provider components in Figure 1 is the WBEM or Windows Management Instrumentation (WMI) server. When the nPartition provider is running on the HP-UX and Linux operating systems, it runs under the Pegasus open-source implementation of the WBEM server. When running on the Microsoft Windows operating system, the nPartition provider takes advantage of the (WMI) server. This allows the nPartition provider to operate as part of an existing framework on the Microsoft Windows operating system.

The next component above the WBEM or WMI Server is the nPartition commands. The nPartition commands component is the command-line interface (CLI) used for managing nPartitions. Commands such as parcreate, parmodify, and parstatus are represented by this component. The nPartition commands use the WBEM or WMI interface to read status information and configure HP nPartition servers. The nPartition commands are available on HP-UX, Linux, and Microsoft Windows.

Finally, the uppermost box in Figure 1 is the Partition Manager (parmgr) graphical user interface (GUI). The Partition Manager GUI provides a web-based interface for viewing the status and making configuration changes to HP nPartition servers. Partition Manager provides graphical hardware and logical views of the entire complex to facilitate system administration. Partition Manager uses the WBEM or WMI interface to read the configuration data for the complex. It makes all changes to the complex configuration using the nPartition commands. This allows administrators to preview the commands that will be executed and even cut and paste the commands into a script or use the GUI as a learning tool. Partition Manager is available on HP-UX, Linux, and Microsoft Windows operating systems.