Server Temperature Monitor?

Shane Hathaway shane at
Mon Feb 2 13:13:36 MST 2009

Joseph Hall wrote:
> On Mon, Feb 2, 2009 at 12:37 PM, Shane Hathaway <shane at> wrote:
>> Also, some server motherboards provide little info via lm_sensors, but
>> provide extensive info via IPMI.  If lm_sensors isn't providing info, we
>> should try IPMI next.
> I'm game. Looking at my distro, I see freeipmi and OpenIPMI. Two
> different packages that do the same thing? Is one better than the
> other? Looks like OpenIPMI is already installed on my server.

The main thing you need is ipmitool, which is an IPMI client.  Try this:

   ipmitool sensor list

Executed from a server with IPMI hardware, that command usually produces 
a nice big table.  If I recall correctly, OpenIPMI provides the kernel 
module to make that work.  IPMI also lets you cycle the power, manage 
the non-volatile system event log (which is not on the hard drive and 
usually gets notified of kernel panics), and do other odd things.

The main thing that's interesting about IPMI is it does not depend on 
any of the main processors.  The BMC, which provides the IPMI functions, 
is a tiny computer-in-a-computer that piggybacks the LAN interface and 
lets other machines issue IPMI commands.  You can use IPMI to monitor 
temperatures, recover from panics, shut down a cluster semi-forcefully, 
etc.  Even SNMP integration apparently exists.

I noticed about 3 years ago that one of the key differences that make a 
motherboard server-class rather than desktop-class is the presence of a 
BMC with IPMI support.


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