Technical Product Specification

Table Of Contents
Server Management Intel
®
Server Board S5400SF TPS
Revision 2.02
Intel order number: D92944-007
52
4.3.2.1 Watchdog Timer Timeout Reason Bits
To implement FRB2, during POST the BIOS determines whether a Integrated BMC watchdog
timer timeout occurred on the previous boot attempt. If it finds that a watchdog timeout did occur,
it determines whether that timeout was an FRB2 timeout, a system management software
(SMS) timeout, or an intentional, timed hard reset.
The timeout-reason bits implemented by the Integrated BMC watchdog are maintained by the
Integrated BMC across system resets and DC power cycles, but not across AC power cycles.
4.3.2.2 Fault Resilient Booting 2 (FRB2)
FRB2 refers to the FRB algorithm that provides for detection of system failures, such as hangs
during POST. The BIOS uses the Integrated BMC watchdog timer to back up its operation
during POST. The BIOS configures the watchdog timer to indicate that the BIOS is using the
timer for the FRB2 phase of the boot operation.
After the BIOS has identified and saved the BSP information, it sets the FRB2 timer use bit and
loads the watchdog timer with the new timeout interval.
If the watchdog timer expires while the watchdog use bit is set to FRB2, the Integrated BMC (if
so configured) logs a watchdog expiration event showing the FRB2 timeout in the event data
bytes. If the BIOS has set the watchdog timeout action as reset, the Integrated BMC then hard
resets the system.
The BIOS is responsible for disabling the FRB2 timeout before initiating the option ROM scan
and before displaying a request for a boot password. If the processor fails and causes an FRB2
timeout, the Integrated BMC resets the system.
As part of its normal operation, the BIOS obtains the watchdog expiration status from the
Integrated BMC. If this status shows an FRB2 timeout expiration, the BIOS creates an entry in
the system event log (SEL) that indicates an FRB2 failure. In the OEM bytes entry in the event
log, the entry includes the last POST code generated during the previous boot attempt in the
OEM bytes of the event entry. FRB2 failure is not reflected in the processor status sensor value.
Although an FRB2 failure causes events to be logged into the SEL, there is no effect on the
front panel LEDs.
4.3.3 Boot Control Support
The Integrated BMC supports the IPMI 2.0 boot control feature. This feature allows the boot
device and boot parameters to be managed remotely.
4.4 Integrated Front Panel User Interface
The Integrated BMC in the Intel
®
6321ESB I/O Controller Hub incorporates the front panel
interface functionality and supports an SSI EB compliant model. The indicators on the Intel
®
6321ESB I/O Controller Hub supported front panels are LEDs. They may be single or bicolor,
depending on the supported model.