// This document is authored using Asciidoctor: // https://asciidoctor.org/
[.lead] A Bash script to rename EFI boot entries
EFI{nbsp}/ https://uefi.org/specifications/[UEFI] is a specification that defines a software interface between an operating system and platform firmware. It is intended by hardware manufacturers to replace the legacy BIOS firmware interface.
In particular this specification allows to define OS boot configurations to be loaded{nbsp}/ executed upon system power on. These boot configurations specify disk partitions to boot from, and are typically identified by their text labels that are listed in "Startup"{nbsp}/ "Boot" EFI setup sections. These boot configurations may be optionally selectable upon system startup.
Operating system installation routines tend to have these boot configuration labels hard-coded and to create them in EFI PROM automatically. So in case a computer has, say, several Ubuntu instances installed, it is also likely to have several identical "ubuntu" boot configuration labels in its EFI menus, causing a kind of confusion.
One might further want to rename boot configurations, so to make them distinguishable, but unfortunately the standard https://github.com/rhboot/efibootmgr[`efibootmgr`] utility has no option for that. It is only possible to delete a boot configuration entry and to re-create it with a new label. Meanwhile, the data that is necessary for re-creating a boot configuration entry is not trivial and requires certain inquiries into EFI configuration and disk partition attributes.
The rename-efi-entry script is designed to help renaming EFI boot configuration entries using efibootmgr utility for
entry deletion and re-creation. It automates querying current EFI configuration and bootable partition data, and also
shaping command line arguments for efibootmgr.
sudo ./rename-efi-entry.bash existing_efi_label new_efi_label [bootnum]
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.Command line arguments
|===
|existing_efi_label
|existing EFI entry label to be renamed; +
a special value of `''` is recognized as a placeholder for "any label", in particular to be used in cases of missing
label
|new_efi_label
|the new label value to be assigned
|bootnum
|conditionally optional: the bootnum value of the EFI entry to be renamed; +
required in case of multiple matching label values, so to avoid ambiguity
|===
E.g.:
sudo ./rename-efi-entry ubuntu 'ubuntu 18.04'
or in case of multiple boot entries labeled as 'ubuntu':
sudo ./rename-efi-entry ubuntu 'ubuntu 18.04' 0001
or in case of missing boot entry label in EFI menu:
sudo ./rename-efi-entry '*' 'ubuntu 18.04' 0001
In case of doubt bootnum values may be clarified using efibootmgr --verbose command, see entries like Boot0001* in
the first column:
[options="nowrap"] .... $ efibootmgr --verbose BootCurrent: 0001 Timeout: 0 seconds BootOrder: 0002,0001,0017,001B,0000,0016,0019,001A,0018 Boot0000 Windows Boot Manager HD(1,MBR,0x5092863d,0x3cde8c,0x1340)/File(\EFI\Microsoft\Boot\bootmgfw.efi)WINDOWS... Boot0001 ubuntu HD(1,GPT,2ffcc127-f6ce-40f0-9932-d1dfd14e9462,0x800,0x100000)/File(\EFI\ubuntu\shimx64.efi) Boot0002 ubuntu HD(1,GPT,cba13b09-d754-4d31-9719-369fa60928d1,0x800,0x100000)/File(\EFI\ubuntu\shimx64.efi) Boot0010 ... ....
Required bootnum values (e.g. 0001 from Boot0001*) may be further identified by checking corresponding uuid
values (e.g. 2ffcc127-f6ce-40f0-9932-d1dfd14e9462) against values provided by sfdisk -d command, e.g.:
[options="nowrap"] .... $ sudo sfdisk -d /dev/sda label: gpt label-id: 0560DAA2-3010-47A2-B083-047C813F0A04 device: /dev/sda unit: sectors first-lba: 34 last-lba: 1953525134
/dev/sda1 : start= 2048, size= 1048576, type=C12A7328-F81F-11D2-BA4B-00A0C93EC93B, uuid=2FFCC127-F6CE-40F0-9932-D1DFD14E9462, name="EFI System Partition" /dev/sda2 : start= 1050624, size= 102400000, type=0FC63DAF-8483-4772-8E79-3D69D8477DE4, uuid=A06790C2-3818-4F57-84EF-4D1B9FFB417E, name="SSD system" /dev/sda3 : start= 103450624, size= 1850073088, type=0FC63DAF-8483-4772-8E79-3D69D8477DE4, uuid=67A374C2-081E-477E-945C-78BE129A2044, name="SSD data" ....
What the script does under the hood, is:
lsblk;uuid values for every disk device using sfdisk;efibootmgr;existing_efi_label value, supplied by the user as command line argument;bootnum if necessary;uuid value from the EFI boot entry to be renamed, and use it to identify the relevant disk partition and its
device name;efibootmgr to delete the existing EFI boot entry and to create a new one with required label;efibootmgr commands.This script was designed to rename EFI boot entries that are related to Linux. It is likely to ignore the other ones. Still it is https://github.com/FroggMaster/EFIRename/blame/603f93f0a3ef9487896d9b6404a1f07eef4ce53a/README.adoc#L109-L110[reported] to deal with Windows 10 entries successfully too.
For an EFI boot entry to be renamed, the related device needs to be attached{nbsp}/ known to the system currently running.
The following boot device types are recognized and honored (see https://wiki.archlinux.org/index.php/Device_file#Block_device_names[Arch Linux : Device file : Block device names]):
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|===
|SCSI family
|e.g. /dev/sda1
|NVMe
|e.g. /dev/nvme0n1p1
|MMC family
|e.g. /dev/mmcblk0p1
|===
Feel free to use, but do it on your risk :)
It may be wise to review the efibootmgr commands before final execution...
The project is issued and distributed under the following licenses: