Re: Missing MCA error messages for bad ECC

Hi,

> On 1 Feb 2026, at 16:35, G. Paul Ziemba <[email protected]> wrote:
> 
> OS: 14.2-STABLE as of 250403
> 
> I seem to have at least one bad ECC DIMM

Check the power supply voltages are within tolerance if you haven’t already.

> and  was expecting to see MCA
> messages in /var/log/messages or to the console (which I have recently
> redirected to /var/log/console.log via syslog.conf:
> 
>    console.info /var/log/console.log
> 
> but I can't find anything in any of my logs. Why am I not seeing them?

If you have the -F variant of the board that supports IPMI, it may be that the BMC is capturing the errors so check the BMC event log. Possibly there is a setting on the BMC to control what gets passed to MCA.

Also check the BIOS event logging; I don’t see settings in the BIOS to control MCA events.

And check the BIOS version is up to date.

> Background:
> 
> Motherboard: Supermicro X11SCA
> CPU: Xeon E-2176G
> Chipset: C246
> Memory: 4x SK Hynix HMA82GU7CJR8N-VK (16GB ECC)
> 
> Bios reports ECC on its startup screen and dmidecode reports
> 
>    Total Width: 72 bits
>    Data Width: 64 bits
> 
> for each of the dimms.
> 
> Amanda started reporting checksum errors on large backup files in its
> holding disk. I discovered that a large file (200GB) on any of three
> disks on this system yields different sha512sum values every time I
> run it on the same file. SMART data looks OK on all disks.
> 
> memtest86+ finds three bad spots in memory, at 42G, 47G and 53G. I have
> 4x16GB dimms installed, so I think that corresponds to two bad dimms.
> 
>    % sysctl hw.mca
>    hw.mca.cmc_throttle: 60
>    hw.mca.force_scan: 0
>    hw.mca.interval: 300
>    hw.mca.maxcount: -1
>    hw.mca.count: 0
>    hw.mca.erratum383: 0
>    hw.mca.intel6h_HSD131: 0
>    hw.mca.amd10h_L1TP: 1
>    hw.mca.log_corrected: 1
>    hw.mca.enabled: 1
> 
> Thanks for any insights.
> -- 
> G. Paul Ziemba
> FreeBSD unix:
> 8:31AM  up 2 days, 14:38, 11 users, load averages: 0.71, 0.43, 0.39
> 


--
Bob Bishop       t: +44 (0)118 940 1243
[email protected]     m: +44 (0)783 626 4518