IBM eServer BladeCenter HS20 Type 8832, Maintenance And Troubleshooting Manual

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Switches and jumpers
Figure 30 shows the location of the switches and jumpers on the system board.
Switches
Table 5 describes the function of each switch on switch block (SW2).
Table 5. Switch block (SW2)
Switch
number Default value
Switch
description
1 through 4 Off Reserved.
5 Off Power-on override. When toggled to On, this switch forces the blade server to turn
on, overriding the power-on button. The power-on override switch should be used for
debug purposes only and should not be used to override management module
control of the server.
6 through 7 Off Reserved
8 Off Power-on password override. Changing the position of this switch bypasses the
power-on password check the next time the blade server is turned on and starts the
Configuration/Setup Utility program so that you can change or delete the power-on
password. You do not need to move the switch back to the default position after the
password is overridden. See “Using passwords” on page 15 for additional
information about the power-on password.
Jumpers
When the BIOS code page jumper (J12) is moved from pins 1 and 2 to pins 2 and
3, you can start the blade server from a backup BIOS page (see “Recovering the
BIOS code” on page 25). The default position is pins 1 and 2.
Note: If you start the blade server from the backup page because the primary
BIOS page has become damaged, you must flash the primary BIOS code.
Switch block
(SW2)
1
2
3
4
5678
OFF
BIOS code page
jumper (J12)
123
4
5
678
O F F
3 2 1
3 2 1
2-1
Normal
3-2
Backup
Light Path
Diagnostics
button
(SW4)
Reserved
(SW3)
Figure 30. System board switches and jumpers
Chapter 7. Field replaceable units
61