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System-board switches

Use this information to locate the system-board switches.

The following illustration shows the location of the switch block on the lower system board.


Graphic illustrating lower system board switches

The following table describes the functions of the switches on switch blocks SW1, SW2, and SW3 on the lower system board.

Note
Unless otherwise noted, the default position for all switches, including those that are listed as Reserved, is Off.
Table 1. Lower system-board switches
Switch numberDescriptionDefinition
SW1-1Password overrideThe default position is Off. Changing this switch to the On position overrides the power-on password.
SW1-2Real time clock (RTC) resetThe default position is Off. Changing this switch to the On position resets the RTC. A momentary toggle is all that is required. To avoid excessive CMOS battery drain, do not leave this switch in the On position.
SW1-3Reserved.Reserved.
SW1-4Force IMM2 updateThe default position is Off. Changing this switch to the On position bypasses the operational firmware image and performs a IMM2 firmware update, if the normal firmware update procedure results in an inoperative IMM2.
Note
Use this jumper only if the normal firmware update procedure fails and the operational firmware image is corrupted. Use of this jumper disables normal IMM2 operation.
SW1-5Boot backup UEFIThe default position is Off. Changing this switch to the On position forces the compute node to boot from the backup UEFI image.
SW1-6Reserved.Reserved.
SW1-7Reserved.Reserved.
SW1-8Reserved.Reserved.
SW2-1Reserved.Reserved.
SW2-2Reserved.Reserved.
SW2-3Reserved.Reserved
SW2-4Trusted Platform Module (TPM) physical presenceThe default position is Off. Changing this switch to the On position indicates physical presence to the TPM.
SW2-5IMM2 TPM physical presenceThe default position is Off. Changing this switch to the On position indicates physical presence of the IMM2 to the TPM.
SW2-6Reserved.Reserved.
SW2-7Reserved.Reserved.
SW2-8Boot backup IMM2When the switch is in the default Off position, the compute node will boot by using the primary IMM2 firmware image. When the switch is in the On position, the compute node will boot by using the recovery IMM2 image.
Note
Use this switch only if the normal firmware update procedure fails and the operational firmware image is corrupted. Use of this switch disables normal baseboard management controller (BMC) operation.
SW3Force non-maskable interrupt (NMI)Pressing this recessed button on the front panel of the compute node causes the compute node to stop doing what it is doing.

The following illustration shows the location of the switch block on the upper system board.


Graphic illustrating upper system board switches

The following table describes the functions of the switches on switch blocks SW1, SW2, and SW3 on the upper system board.

Note
Unless otherwise noted, the default position for all switches, including those that are listed as Reserved, is Off.
Table 2. Upper system-board switches
Switch numberDescriptionDefinition
SW1-1Password overrideThe default position is Off. Changing this switch to the On position overrides the power-on password.
SW1-2Real time clock (RTC) resetThe default position is Off. Changing this switch to the On position resets the RTC. A momentary toggle is all that is required. To avoid excessive CMOS battery drain, do not leave this switch in the On position.
SW1-3Reserved.Reserved.
SW1-4Force IMM2 updateThe default position is Off. Changing this switch to the On position bypasses the operational firmware image and performs a IMM2 firmware update, if the normal firmware update procedure results in an inoperative IMM2.
Note
Use this jumper only if the normal firmware update procedure fails and the operational firmware image is corrupted. Use of this jumper disables normal IMM2 operation.
SW1-5Boot backup UEFIThe default position is Off. Changing this switch to the On position forces the compute node to boot from the backup UEFI image.
SW1-6Reserved.Reserved.
SW1-7Reserved.Reserved.
SW1-8Reserved.Reserved.
SW2-1Reserved.Reserved.
SW2-2Reserved.Reserved.
SW2-3Reserved.Reserved.
SW2-4Trusted Platform Module (TPM) physical presenceThe default position is Off. Changing this switch to the On position indicates physical presence to the TPM.
SW2-5IMM2 TPM physical presenceThe default position is Off. Changing this switch to the On position indicates physical presence of the IMM2 to the TPM.
SW2-6Reserved.Reserved.
SW2-7Reserved.Reserved.
SW2-8Boot backup IMM2When the switch is in the default Off position, the compute node will boot by using the primary IMM2 firmware image. When the switch is in the On position, the compute node will boot by using the recovery IMM2 image.
Note
Use this switch only if the normal firmware update procedure fails and the operational firmware image is corrupted. Use of this switch disables normal baseboard management controller (BMC) operation.
SW3Force non-maskable interrupt (NMI)Pressing this recessed button on the front panel of the compute node causes the compute node to stop doing what it is doing.