Manage servers with IPMI: most rack-optimized servers and blades include some form of a built-in server processor technology like IPMI

Communications News, July, 2005 by Tom Wingfield

For decades, the challenge for network and IT managers has been to deliver high service levels at the lowest possible cost. Since IT and networking hardware can fail, one way to reduce costs and improve performance is to provide a way to remotely access, diagnose and restore equipment without sending technicians to the device.

Out-of-band infrastructure (OOBI) technologies emerged to meet this need for remote IT administration. These out-of-band components, such as serial console servers and KVM switches, help reduce operational costs by lessening the need to physically touch disconnected equipment in order to restore it to the network.

Some server vendors took a different approach by embedding a chip called a service processor on server motherboards, which allowed IT administrators to access, diagnose and restore frozen servers. Since the first service processor technologies were vendor specific, however, they added to IT management complexity by limiting the source of management technologies to a single vendor. As a result, demand for vendor-independent service processors emerged. Intelligent platform management interface (IPMI) was introduced to provide a way to manage servers in today's complex data centers.

IPMI is an open-service processor standard adopted by more than 150 companies. Most rack-optimized servers and blade computing platforms include some form of a built-in server processor technology like IPMI.

In IPMI jargon, the service processor is called the baseboard management controller (BMC). IPMI works by interfacing with the BMC, which extends management capabilities in the server system and operates independent of the main processor by monitoring the on-board instrumentation, such as temperature sensors, CPU status, fan speed and voltages. Through the BMC, IPMI also allows administrators to control power to the server, and remotely access BIOS configuration and operating system console information.

To be useful, IPMI-based server management needs to support a variety of servers regardless of operating system or vendor. Most server vendors include IPMI in their platforms but hide it behind proprietary vendor-specific features. For all its advantages, IPMI also has limitations that affect its value within the enterprise, including security, scalability and integration issues.

In the IPMI protocol, security is defined between the BMC and an IPMI local workstation by user name, password and authorization level. This does not provide enough security for most organizations with enterprise environments that require password compliance, server-based authentication and access control. Before these organizations can effectively use IPMI, remote access to the BMC must be integrated with the security architectures already in place.

Therefore, IPMI management should include support for widely used server-based authentication protocols (LDAP, RADIUS, TACACS , NIS, Kerberos), industry-standard encryption (Secure Shell for command line access and Secure Socket Layer for Web-based access), and enterprise-compliant access and logging for both end-users and management applications. IPMI security also needs a provision for a local password backup system in case authentication failures occur.

In large enterprises, IPMI managers need to automatically process information from the BMC, such as automatic alerts and functionality, to be able to remotely and efficiently monitor large numbers of servers with IPMI technology. Large enterprises also require an IPMI system that provides administrators with a consolidated view of all connected servers to simplify server administration. This is usually accomplished with a database that maps the server network to provide a consolidated view of all managed servers, and includes group filters that display servers by location or operating system.

This level of functionality is necessary to simplify how administrators view, find and access individual servers. It also ensures access to servers can be controlled to comply with security policies.

An effective IPMI strategy needs to include a way to integrate IPMI management with other out-of-band technologies. It should simplify IT infrastructure management and increase operational efficiency. Some systems currently exist that integrate IPMI management into a complete remote IT administration system-including serial console servers, KVM and remote power appliances-usually through an out-of-band infrastructure manager.

By integrating IPMI management into a comprehensive OOBI system, administrators can consolidate remote access and administration for all of their hardware IT assets into a single view. The benefits of this approach include reduced operational costs and business risks, increased IT asset and personnel productivity, and increased security throughout the enterprise.

For most enterprises, an effective IPMI management strategy involves integrating IPMI management and access into an out-of-band infrastructure manager. This approach addresses the following issues: