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@@ -9,7 +9,7 @@ still be bootable.
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== Example ==
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== Example ==
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-Lets assume we have QEMU machine with two NICs (virtio, e1000) and two
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+Let's assume we have a QEMU machine with two NICs (virtio, e1000) and two
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disks (IDE, virtio):
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disks (IDE, virtio):
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qemu -drive file=disk1.img,if=none,id=disk1
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qemu -drive file=disk1.img,if=none,id=disk1
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@@ -20,7 +20,7 @@ qemu -drive file=disk1.img,if=none,id=disk1
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-netdev type=user,id=net1 -device e1000,netdev=net1,bootindex=1
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-netdev type=user,id=net1 -device e1000,netdev=net1,bootindex=1
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Given the command above, firmware should try to boot from the e1000 NIC
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Given the command above, firmware should try to boot from the e1000 NIC
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-first. If this fails, it should try the virtio NIC next, if this fails
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+first. If this fails, it should try the virtio NIC next; if this fails
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too, it should try the virtio disk, and then the IDE disk.
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too, it should try the virtio disk, and then the IDE disk.
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== Limitations ==
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== Limitations ==
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@@ -28,7 +28,7 @@ too, it should try the virtio disk, and then the IDE disk.
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1. Some firmware has limitations on which devices can be considered for
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1. Some firmware has limitations on which devices can be considered for
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booting. For instance, the PC BIOS boot specification allows only one
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booting. For instance, the PC BIOS boot specification allows only one
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disk to be bootable. If boot from disk fails for some reason, the BIOS
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disk to be bootable. If boot from disk fails for some reason, the BIOS
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-won't retry booting from other disk. It still can try to boot from
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+won't retry booting from other disk. It can still try to boot from
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floppy or net, though.
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floppy or net, though.
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2. Sometimes, firmware cannot map the device path QEMU wants firmware to
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2. Sometimes, firmware cannot map the device path QEMU wants firmware to
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@@ -36,8 +36,8 @@ boot from to a boot method. It doesn't happen for devices the firmware
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can natively boot from, but if firmware relies on an option ROM for
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can natively boot from, but if firmware relies on an option ROM for
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booting, and the same option ROM is used for booting from more then one
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booting, and the same option ROM is used for booting from more then one
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device, the firmware may not be able to ask the option ROM to boot from
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device, the firmware may not be able to ask the option ROM to boot from
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-a particular device reliably. For instance with PC BIOS, if a SCSI HBA
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+a particular device reliably. For instance with the PC BIOS, if a SCSI HBA
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has three bootable devices target1, target3, target5 connected to it,
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has three bootable devices target1, target3, target5 connected to it,
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the option ROM will have a boot method for each of them, but it is not
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the option ROM will have a boot method for each of them, but it is not
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possible to map from boot method back to a specific target. This is a
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possible to map from boot method back to a specific target. This is a
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-shortcoming of PC BIOS boot specification.
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+shortcoming of the PC BIOS boot specification.
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