IPMI problem with FAI and wheezy

[Steffen Grunewald]

Hi,

I'm at my wits' end now with this old system, perhaps one of you can come
up with another idea:

The hardware is somewhat old, SuperMicro H8SSL board with IPMI card (BMC)
looped into eth0 (Broadcom Tigon3).

Excerpts from the demsg file:
[    0.000000] Linux version 3.2.0-3-amd64 (Debian 3.2.23-1) (debian-kernel at lists.debian.org) (gcc version 4.6.3 (Debian 4.6.3-8) ) #1 SMP Mon Jul 23 02:45:17 UTC 2012
[    0.000000] ACPI: FACP 000000007ffe0290 000F4 (v03 A M I  OEMFACP  12000606 MSFT 00000097)
[    0.000000] ACPI: DSDT 000000007ffe0410 033A8 (v01  0ABSW 0ABSW005 00000005 INTL 02002026)
[    0.884954] tg3 0000:02:03.0: eth0: Tigon3 [partno(BCM95704A6) rev 2100] (PCIX:133MHz:64-bit) MAC address xx:xx:xx:xx:xx:xx

I used to set "console=ttyS1,19200n1" in the pxelinux.cfg file, and watch
FAI running via serial-over-LAN, but that stops right at the beginning -
and the IPMI card cannot be reached afterwards, not by rebooting, nor by
applying other tricks. The only way to get the connection back is power-
cycling the whole box.

This behaviour did not show up with Squeeze (2.6.32-5 kernel).

I'm suspecting a change in the handling of the eth0/BMC bridge by the tg3
driver, but that's only part of the story: it gets worse.

Trying to shut down the machine (actually, a whole set of machines, all
behaving the same, so it's not a single fault), by running "shutdown -h now", 
will not halt but reboot it.
The only way to reliably switch it off seems to be to run "ipmitool chassis
power soft", then "shutdown -h now".
The machine will then stay off for exactly 24 hours, then magically restart.

Needless to say I didn't change any BIOS settings, nor implemented kind of
a watchdog on the BMC.

Is there anything I can do to nail down the problem?

Thank you in advance for your suggestions.

Steffen