#30 Using ipmiutil to restart unresponding BMC

[Egorshev Dmitry]

Hello,
I'm looking for the way to restart unresponding BMC without impacting running windows system.
Can you please clarify, what reset -k command will do to the server? Will it restart only BMC or whole system? If it is latter, what the difference with reset -r?
Also, will BMC restart change any settings, like IP-address, to default values?
Thanks in advance!

[Andy Cress]

The IPMI firmware runs in a completely separate space, with access only to the hardware sensors and controls, not to the main CPU and memory. So software in the main CPU can send requests to the firmware, but not vice-versa. The firmware continues running via the 5V standby power as long as the system is plugged in to a power source .

The reset -k sends a cold reset to the BMC firmware for the firmware to reboot itself. This does not impact the main CPU and memory. The BMC restart typically takes from 10 to 30 seconds. Any software which is trying to send requests to the firmware will time out during this reset. On a Windows system, only some management software using WMI would even notice.

The reset -r sends a request to the BMC firmware to apply a hard reset control to the entire system, as if the power button had been cycled. This will reboot the entire system, except the firmware.

For reset -k, most firmware vendors preserve the IPMI LAN configuration (Intel, Dell, Lenovo/IBM, etc.). even SuperMicro saves the LAN IP. If by some chance your firmware vendor does not preserve it, you can always re-apply it after the reset using 'ipmiutil lan -e -I <ip> [options]'.</ip>