I have a few servers with IBM BMC (Baseboard Management Controller). I'd like to power cycle the BMC without restarting the server. Is this possible? How?
Note: On one of them, the web interface is down; so I'd need to either do this by physically restarting the BMC (not sure how to do this - even the power button on the server isn't supposed to recycle the BMC, I believe) or via the UDP or SNMP interface (again, not sure how to do that either)
The simplest way is if you can log onto the server, run as root:
If you can't connect to the BMC via web, ssh, IPMI, telnet, or other connection mechanism that you have configured, then the only way to reset the BMC for sure is to power the computer down and then pull the power inputs. Many BMCs (or iLO or eLOM or whatever) don't reset themselves when the computer reboots or powers off.
For anyone with a similar issue, here is the ipmiutil command for issuing a cold reset on the BMC without rebooting the server:
I personally use
ipmiutil
overipmitool
when possible as it can run without IPMI drivers installed. I have had several instances where the Linux IPMI modules locked up due an issue with the BMC. This prevented ipmitool from running but I was still able to use ipmiutil in "driverless mode", which it reverts to automatically. The only downside is that, unlike ipmitool, ipmiutil is most likely not already installed. It should be available to install using the yum/apt-get repos included with most distros though.I don't know the IBM ones but on HP servers you can often ssh into their iLO if the web front end is broken and vice-versa. If you do neither then I think it'll be a full system power-off/on.
Assuming you assigned an IP to the BMC, you can telnet in and run this tool from IBM. It has power and reset options. The hitch is, I don't know if those commands include the actual BMC - tragic. But it may give you a starting point.
http://idolinux.blogspot.com/2008/11/ibm-baseboard-management-controller.html
http://www-947.ibm.com/support/entry/portal/docdisplay?brand=5000008&lndocid=MIGR-64636
Not sure only BMC reboot.
But if u want to reboot the Remote Managemenet then manually and physically do an AC power off.. Disconnect the both redundant AC power supplies. The whole system will be powered off.