Supermicro IPMI sensors not present after shutdown

Welcome to Supermicro, where the docs are inconsistent and often wrong. What I typically end up doing is digging around on ftp://ftp.supermicro.com until I find something that seems useful.

In your case, I'd suggest you check for upgrades to the actual BIOS before you try anything else. The IPMI BIOS and the real BIOS appear to be closely linked, and upgrading the real one may help.

From there, I'd suggest you take a look at the tools in ftp://ftp.supermicro.com/utility/ , one of them will probably work for you, even though none explicitly claim to support your motherboard. The 'IPMI FW flash tools' directory is probably where I'd start.

I should note that it's possible to brick the motherboard or IPMI controller by using the wrong firmware flash tool. The only people that can tell you which tool is actually correct is Supermicro themselves.

It looks like your machine comes with Integrated IPMI. This means that your BMC may be configured to use either the dedicated IPMI port on the back of the machine, or it may share IPMI with one of the existing LAN ports (This is called sideband).

Read the manual, and make sure that your system is configured to use either dedicated IPMI (This is my preference) or IPMI sideband. Make sure it is what you expect it to be.

The Supermicro BMC sometimes tries to autodetect the IPMI port, and sometimes makes the wrong decision. I've actually had to do the following to get IPMI working:

1. Configure IPMI to use either dedicated IPMI or sideband IPMI.

2. (This is the tricky part) Unplug power from the machine. Let the capacitors bleed. Simply powering off the machine is not sufficient, since IPMI is intended to work when your machine is powered off. In fact, Embedded_BMC_IPMI.pdf says:

   Note 1: If you wish to use the IPMI-dedicated LAN port for your network connections, be sure to connect an RJ45 cable to your dedicated LAN port before you activate the BMC (at fi rst power-on or cold reset). Otherwise, the BMC will look for a shared LAN port to connect to if the IPMI-dedicated LAN cable is not detected upon BMC activation.

3. Plug in an ethernet cable into the correct IPMI port. The link layer must be active-- the other end must be plugged into an active port on your network switch. e.g. Electrons must be flowing over the wire, so that the BMC can detect an active link.

4. Power the machine back on.