EFI Shell

1.2. Itanium Systems — The EFI Shell

Before you start to install Red Hat Enterprise Linux on an Itanium, you must have a basic understanding of the EFI Shell, what it does, and the information it can provide.

The EFI Shell is a console interface used to launch applications (such as the Red Hat Enterprise Linux installation program), load EFI protocols and device drivers, and execute simple scripts. It is similar to a DOS console and can only access media that is FAT16 (VFAT) formatted.

The EFI Shell also contains common utilities that can be used on the EFI system partition. These utilities include edit, type, cp, rm, and mkdir. For a list of utilities and other commands, type help at the EFI Shell prompt.

The EFI Shell contains a boot loader called ELILO. Additional information on EFI can be found at the following URL:

http://developer.intel.com/technology/efi/index.htm

1.2.1. Itanium Systems — EFI Device Names

The map command can be used to list all devices and file systems that EFI can recognize. When your Itanium system boots into the EFI shell, it probes your system in the following order:

1. LS-120 drive (if it contains media)

2. IDE hard drives on the primary IDE interface

3. IDE hard drives on the secondary IDE interface

4. SCSI hard drives on the SCSI interface

5. CD-ROM drives on the IDE interface

6. CD-ROM drives on the SCSI interface

To view the results of this system poll, type the following command at the EFI Shell prompt:

map

The output is listed in the order the system was probed. So, all FAT16 file systems are listed first, then IDE hard drives, then SCSI hard drives, then IDE CD-ROM drives, and finally SCSI CD-ROM drives.

For example, output of the map command might look like the following:

Device mapping table fs0 : VenHw(Unknown Device:00)/HD(Part1,Sig00000000) fs1 : VenHw(Unknown Device:80)/HD(Part1,Sig00000000) fs2 : VenHw(Unknown Device:FF)/CDROM(Entry1)/HD(Part1,Sig00000000) blk0 : VenHw(Unknown Device:00) blk1 : VenHw(Unknown Device:00)/HD(Part1,Sig00000000) blk2 : VenHw(Unknown Device:80) blk3 : VenHw(Unknown Device:80)/HD(Part1,Sig00000000) blk4 : VenHw(Unknown Device:80)/HD(Part2,Sig00000000) blk5 : VenHw(Unknown Device:80)/HD(Part3,Sig00000000) blk6 : VenHw(Unknown Device:80)/HD(Part3,Sig00000000)/HD(Part1,Sig725F7772) blk7 : VenHw(Unknown Device:FF) blk8 : VenHw(Unknown Device:FF)/CDROM(Entry1) blk9 : VenHw(Unknown Device:FF)/CDROM(Entry1)/HD(Part1,Sig00000000)

In this example, there is an LS-120 diskette in the LS-120 drive as well as a CD-ROM in the CD-ROM drive. All the listings beginning with fs are FAT16 file systems that EFI can read. All the listings beginning with blk are block devices that EFI recognizes. Both the file systems and block devices are listed in the order they are probed. Therefore, fs0 is the system partition on the LS-120, fs1 is the system partition on the hard drive, and fs2 is the system partition on the CD-ROM.

1.2.2. Itanium Systems — EFI System Partition

When partitioning your hard drive for Linux, you must create a system partition that is FAT16 (VFAT) formatted and has a mount point of /boot/efi/. This partition contains the installed Linux kernel(s) as well as the ELILO configuration file (elilo.conf). The elilo.conf file contains a list of kernels from which you can boot your system.