grub: Device syntax
13.1 How to specify devices
===========================
The device syntax is like this:
(DEVICE[,PARTMAP-NAME1PART-NUM1[,PARTMAP-NAME2PART-NUM2[,...]]])
'[]' means the parameter is optional. DEVICE depends on the disk
driver in use. BIOS and EFI disks use either 'fd' or 'hd' followed by a
digit, like 'fd0', or 'cd'. AHCI, PATA (ata), crypto, USB use the name
of driver followed by a number. Memdisk and host are limited to one
disk and so it's refered just by driver name. RAID (md), ofdisk
(ieee1275 and nand), LVM (lvm), LDM, virtio (vdsk) and arcdisk (arc) use
intrinsic name of disk prefixed by driver name. Additionally just
"nand" refers to the disk aliased as "nand". Conflicts are solved by
suffixing a number if necessarry. Commas need to be escaped. Loopback
uses whatever name specified to 'loopback' command. Hostdisk uses names
specified in device.map as long as it's of the form [fhc]d[0-9]* or
hostdisk/<OS DEVICE>. For crypto and RAID (md) additionally you can use
the syntax <driver name>uuid/<uuid>. For LVM additionally you can use
the syntax lvmid/<volume-group-uuid>/<volume-uuid>.
(fd0)
(hd0)
(cd)
(ahci0)
(ata0)
(crypto0)
(usb0)
(cryptouuid/123456789abcdef0123456789abcdef0)
(mduuid/123456789abcdef0123456789abcdef0)
(lvm/system-root)
(lvmid/F1ikgD-2RES-306G-il9M-7iwa-4NKW-EbV1NV/eLGuCQ-L4Ka-XUgR-sjtJ-ffch-bajr-fCNfz5)
(md/myraid)
(md/0)
(ieee1275/disk2)
(ieee1275//pci@1f\,0/ide@d/disk@2)
(nand)
(memdisk)
(host)
(myloop)
(hostdisk//dev/sda)
PART-NUM represents the partition number of DEVICE, starting from
one. PARTNAME is optional but is recommended since disk may have
several top-level partmaps. Specifying third and later component you
can access to subpartitions.
The syntax '(hd0)' represents using the entire disk (or the MBR when
installing GRUB), while the syntax '(hd0,1)' represents using the first
partition of the disk (or the boot sector of the partition when
installing GRUB).
(hd0,msdos1)
(hd0,msdos1,msdos5)
(hd0,msdos1,bsd3)
(hd0,netbsd1)
(hd0,gpt1)
(hd0,1,3)
If you enabled the network support, the special drives
'(PROTOCOL[,SERVER])' are also available. Supported protocols are
'http' and 'tftp'. If SERVER is omitted, value of environment variable
'net_default_server' is used. Before using the network drive, you must
initialize the network. ⇒Network, for more information.
If you boot GRUB from a CD-ROM, '(cd)' is available. ⇒Making a
GRUB bootable CD-ROM, for details.
Info Catalog
grub: Filesystem
grub: File name syntax