Clock Feature; Mmb, Bios, And Bmc Time Management - Fujitsu PRIMEQUEST 1000 Series General Description Manual

PRIMEQUEST 1000 Series General Description
CHAPTER 4 Functions Provided by the PRIMEQUEST 1000 Series
4.6

Clock Feature

This section describes the clock feature of the PRIMEQUEST 1000 series.
4.6.1

MMB, BIOS, and BMC time management

This section describe the management of the MMB, BIOS/OS, and BMC times.
MMB
The MMB has an RTC (real-time clock) and manages the time of day independently. The RTC can be set by a user.
Notes
The MMB time and the partition time are managedseparately by independent clocks.
The MMB clock does not report or adjust the partitiontime. Keep the MMB time and the partition time the same,
or at least close, becausethey are needed for the following cases:
- When checking the MMB log against the OS log in a partition at the hardware failure time
- When conducting a system audit or security audit
- When an error occurs regarding the maintenance time of the battery in a partition
Use either of the following ways to adjust the times.
- Adjust the time manually from the MMB Web-UI.
- Use the NTPclient function of the MMB to adjust the time.
BIOS/OS
The operating system reads the built-in RTC contained in the ICH (ICH-RTC) at the boot time. It manages the time
of day by itself, using the timer when it is running. The ICH-RTC is driven by the battery on the SB (referred to
below as the SB battery).
BMC
The BMC has a built-in RTC.
Notes
- When the SB battery runs out, the BIOS applies the MMB time to the ICH-RTC. It also applies any time
difference between the ICH-RTC time and MMB time.
For example, if the ICH-RTC time is set 30 minutes ahead of the MMB time, and the MMB time is applied
to the ICH-RTC because of an SB battery power shortage, a time value that is 30 minutes ahead of the MMB
time is applied to the ICH-RTC.
The time difference will also be applied in a manual correction of the MMB time
- Immediately after SB mounting or AC power-on, the RTC value of the BMC is counted from the initial value.
To synchronize the BMC time (internal clock) with the RTC of the MMB, the MMB reports the RTC time
to the BMC and initializes the BMC time. The BMC time will also be corrected in a manual correction of
the MMB time.
- A partition configured with more than one SB (2 or more SBs) must use NTP.
- If an SB failure causes SB degradation and the Home SB is replaced, the operating system reads the RTC
value of the new Home SB. This may result in a difference between the times before and after the Home SB
replacement.
- When the Reserved SB is used, be sure to use NTP.
102 C122-B022-11EN