Oracle X6 series, Administration Manual, Page: 95 / 126

Option ROM and I/O Space Allocation 95
Option ROM and I/O Space Allocation
Bootable devices such as onboard I/O or PCIe express modules require option ROM and I/O
space to boot. However the total option ROM and I/O space for the system is limited by the PC
architecture and is allocated automatically when the system is booted. If your system includes
many potentially bootable devices, you must decide which ones you wish to boot from, and
configure the BIOS to allocate these resources to them.
Option ROM is also required to run some configuration utilities, such as RAID configuration
utilities.
Note -
These limitations apply to systems configured to use Legacy BIOS Boot Mode. Systems
configured to use UEFI Boot Mode do not normally encounter option ROM or I/O space
limitations.
This section includes:
■
“Determine Whether You Need to Allocate Option ROM and I/O Space” on page 95
■
“Configure Option ROM and I/O Space Allocation” on page 96
Determine Whether You Need to Allocate Option ROM
and I/O Space
If you add a PCIe express module to your server, when the server boots, the BIOS might not be
able to allocate option ROM or I/O space to all the devices that require it.
If this happens, when you boot, POST generates error messages. These identify any devices that
have not had option ROM or I/O space allocated.
1.
Power on the system to start the BIOS.
2.
During POST, look for one or more messages, such as these.
■
For option ROM, the messages look like this:
Warning: Out of option ROM space for <
device path | address
>