Baseboard Management Controller (BMC): What is it?

BMC (Baseboard Management Controller) can be utilized to manage the running status of the server locally and remotely. Featuring the visual console interface, it’s easy for the administrator to manage the hardware and do troubleshooting.

What is Baseboard Management Controller (BMC)?

A baseboard management controller (BMC) is a specialized service processor that monitors the physical state of a computer, network server, or other hardware device using sensors and communicating with the system administrator through an independent connection. The BMC is part of the Intelligent Platform Management Interface (IPMI) and is usually contained in the motherboard or main circuit board of the device to be monitored.

How does Baseboard Management Controller (BMC) work?

The sensors of a BMC measure internal physical variables such as temperature, humidity, power-supply voltage, fan speeds, communications parameters, and operating system (OS) functions. If any of these variables happens to stray outside specified limits, the administrator is notified. That person can then take corrective action by remote control. The monitored device can be power cycled or rebooted as necessary. In this way, a single administrator can remotely manage numerous servers and other devices simultaneously, saving on the overall operating cost of the network and helping to ensure its reliability.

Why do you need it?

The key advantage of a BMC is that allows a system administrator to perform many different monitoring and management tasks remotely without having to be physically located next to and connected to the system – such as power cycling, installing BIOS or firmware updates, and monitoring fan speeds and temperatures. The BMC will also notify the administrator (via email or text message) if there is hardware failure (such as a hard drive, fan, or PSU that needs replacing) or if there is another kind of error or fault.

The baseboard management controller is extremely efficient labor and time-saving feature – the administrator no longer needs to physically connect with each server in the rack to perform maintenance tasks. In modern data centers which could have hundreds of racks and thousands of servers, it would be impossible to live without it. As a result, all modern servers and other devices used in a data center (such as switches, storage devices, power supply devices, etc.) now have a BMC.

Tasks performed by Baseboard Management Controller

Tasks that the BMC perform includes:

• Blade inventory
• Monitor sensors (blade voltages, temp, fans, etc.)
• Log events for failure analysis.
• LED guided diagnostics
• Power management
• Provide remote management capabilities (IPMI, KVM, vMedia (using USB), and SOL(Serial over LAN))

The baseboard management controller has its IP address, which can be accessed with a special web interface. The BMC helps in reducing manpower that would otherwise be needed to monitor large networks or servers, and it indirectly helps in bringing reliability to the overall monitoring of the network.

Conclusion

Out-of-band management for servers is truly one of the largest innovations in the data center. Instead of having to physically visit a data center, plugin or switch a keyboard, video display, and mouse, or power on/ off a machine, one can now do it remotely. One can use BMCs to remotely monitor and manage large clusters of servers and automate IT processes. At the same time, even a single colocated server can benefit from a baseboard management controller by dramatically cutting remote hands costs. While BMCs present a surface that rightly is the focus of many security researchers, it is also a technology that underpins modern infrastructure from the smallest to largest server deployments.