SOLVED Supermicro IPMI sensors read "Not Present!"

[fmyhr]

First, many thanks to Ericloewe for his excellent Supermicro X10/X11 motherboard FAQ.

I was still fighting this problem with IPMI sensors even after flashing my X10SLM+-F to latest IPMI firmware and BIOS and resetting IPMI to factory default. Strangely, sometimes the sensors would work, but then they'd go away again. After too much time spent removing power, removing/replacing CMOS battery, clearing CMOS, moving jumpers and flashing, and reading FAQs on the Supermicro website, the pattern finally hit me: the IPMI sensors never worked while the computer sat in BIOS Setup; they did work when booted to FreeDOS on a USB flash drive. Several of the Supermicro FAQs address this issue: only 1 program / service can directly monitor the hardware sensors at a time. So lm_sensors must be set to read values from IPMI, not directly from hardware, for example. It finally hit me when I noticed different fan speeds in BIOS Setup vs. booted to DOS: BIOS Setup is accessing the hardware sensors directly, preventing IPMI sensors from working. So really my "problem" had been a false alarm: just don't expect IPMI sensors to work while in BIOS Setup. This may well be obvious to old hands with IPMI, but it sure wasn't to me. Posting here to hopefully save other IPMI newbies some time and hair. :p

 

[Phlogi]

Thanks, this is interesting indeed. Could this also be true for a booted OS like debian with lm_sensors?

 

[Ericloewe]

I should add that to the FAQ. I should've done it loooong ago, since we've known about this for a while.

 

[Phlogi]

Thanks, this is interesting indeed. Could this also be true for a booted OS like debian with lm_sensors?

Don't worry my issue was resolved by resetting the IPMI settings.

 

[Scootter]

@fmyhr

Just wanted to say a big thank you! This was driving me nuts trying to solve on my own and this post was the first result in Google.