MX Linux Forum • No more boot partition

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No more boot partition

Posted: Sun Nov 10, 2024 8:11 am

by lachelp

Hello all,

I had a working MX 23.1 system on my laptop which was working fine and dual-booting with BlissOS v16 which this morning decided to stop working. I could not find a way to recover the BlissOS so I decided to reinstall and after this install the grub menu & theme changed to BlissOSes with no mention of MX. My next step after multiple failed attempts to recover the old grub menu was to format the /boot partition and delete the BlissOS folder in the /home directory.

After this, no grub menu at all, not even an option to boot from the SSD appears in the boot selection menu from the BIOS. I've tried both the AntiX and MX version of boot-repair from live USBs multiple times and ways to no avail and I attempted to look for the fstab section for the /boot partition's new UUID but that does not exist.

I have the drive configured like so:
sda1 -- /boot -- fat32
sda2 -- / -- ext4
sda3 -- /home -- ext4

Any help to get this system back up would be very much appreciated.

Signed,
Frusterbrated Newbie

Re: No more boot partition

Posted: Sun Nov 10, 2024 8:17 am

by Eadwine Rose

With all help requests, as per forum rules (which, if you haven't, please read), please share your full Quick System Info, do not edit.
If need be, you can do this using the LiveUSB, thanks.

Re: No more boot partition

Posted: Sun Nov 10, 2024 8:43 am

by Kermit the Frog

Till you post the QSI (as we don't know yet whether it's uefi or legacy etc..):

I wish you just run sudo update-grub on the other distro to make it detect MX ..

Roughly:

The /boot partition needs to be ext4 , not fat32

fat32 is for ESP (when it's uefi) , that also needs to have the flag(s) esp (and) boot ... (In fact the boot flag is needed by Windows, not Linux, we do it just by the way)

Re: No more boot partition

Posted: Sun Nov 10, 2024 9:54 am

by fehlix

Booting from MX Live USB and post QSI would be helpfull.
I guess even with "cleared" boot partition, you would just need to use
the tool "Chroot Rescue", to "visit" the non-bootable "MX linux" installation,
and reinstall a kernel, followed by reinstall grub boot loader.
Perhaps also partition layout, shown with these commands running within terminal:

Code: Select all

lsblk -f

and

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sudo parted --list

Maybe also post content of the file /etc/fstab,
found on the "/" root partition on the internal drive.

Re: No more boot partition

Posted: Sun Nov 10, 2024 5:17 pm

by lachelp

Thanks for the quick replies guys, here's my QSI from a 'live' USB boot:

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System:
  Kernel: 6.1.0-13-amd64 [6.1.55-1] arch: x86_64 bits: 64 compiler: gcc v: 12.2.0
    parameters: BOOT_IMAGE=/antiX/vmlinuz quiet splasht nosplash
  Desktop: Xfce v: 4.18.1 tk: Gtk v: 3.24.36 info: xfce4-panel wm: xfwm v: 4.18.0 vt: 7
    dm: LightDM v: 1.26.0 Distro: MX-23.1_x64 Libretto October 15  2023 base: Debian GNU/Linux 12
    (bookworm)
Machine:
  Type: Laptop System: ASUSTeK product: VivoBook_ASUSLaptop X409JA_P1410CJA v: 1.0
    serial: <superuser required>
  Mobo: ASUSTeK model: X409JA v: 1.0 serial: <superuser required> UEFI: American Megatrends
    v: X409JA.310 date: 08/12/2021
Battery:
  ID-1: BAT0 charge: 15.0 Wh (74.6%) condition: 20.1/32.1 Wh (62.6%) volts: 7.9 min: 7.9
    model: ASUSTeK ASUS Battery type: Li-ion serial: N/A status: discharging cycles: 989
CPU:
  Info: model: Intel Core i3-1005G1 bits: 64 type: MT MCP arch: Ice Lake gen: core 10 level: v4
    note: check built: 2019-21 process: Intel 10nm family: 6 model-id: 0x7E (126) stepping: 5
    microcode: 0xA6
  Topology: cpus: 1x cores: 2 tpc: 2 threads: 4 smt: enabled cache: L1: 160 KiB
    desc: d-2x48 KiB; i-2x32 KiB L2: 1024 KiB desc: 2x512 KiB L3: 4 MiB desc: 1x4 MiB
  Speed (MHz): avg: 1170 high: 1300 min/max: 400/3400 scaling: driver: intel_pstate
    governor: powersave cores: 1: 922 2: 1300 3: 1158 4: 1300 bogomips: 9523
  Flags: avx avx2 ht lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx
  Vulnerabilities:
  Type: gather_data_sampling status: Vulnerable: No microcode
  Type: itlb_multihit status: KVM: VMX disabled
  Type: l1tf status: Not affected
  Type: mds status: Not affected
  Type: meltdown status: Not affected
  Type: mmio_stale_data status: Vulnerable: Clear CPU buffers attempted, no microcode; SMT
    vulnerable
  Type: retbleed mitigation: Enhanced IBRS
  Type: spec_rstack_overflow status: Not affected
  Type: spec_store_bypass mitigation: Speculative Store Bypass disabled via prctl
  Type: spectre_v1 mitigation: usercopy/swapgs barriers and __user pointer sanitization
  Type: spectre_v2 mitigation: Enhanced IBRS, IBPB: conditional, RSB filling, PBRSB-eIBRS: SW
    sequence
  Type: srbds status: Vulnerable: No microcode
  Type: tsx_async_abort status: Not affected
Graphics:
  Device-1: Intel Iris Plus Graphics G1 vendor: ASUSTeK driver: i915 v: kernel arch: Gen-11
    process: Intel 10nm built: 2019-21 ports: active: eDP-1 empty: HDMI-A-1 bus-ID: 00:02.0
    chip-ID: 8086:8a56 class-ID: 0300
  Device-2: IMC Networks USB2.0 VGA UVC WebCam type: USB driver: uvcvideo bus-ID: 1-5:4
    chip-ID: 13d3:5a11 class-ID: 0e02
  Display: x11 server: X.Org v: 1.21.1.7 compositor: xfwm v: 4.18.0 driver: X:
    loaded: modesetting unloaded: fbdev,vesa dri: iris gpu: i915 display-ID: :0.0 screens: 1
  Screen-1: 0 s-res: 1366x768 s-dpi: 96 s-size: 361x203mm (14.21x7.99") s-diag: 414mm (16.31")
  Monitor-1: eDP-1 model: AU Optronics 0x723c built: 2017 res: 1366x768 hz: 60 dpi: 112
    gamma: 1.2 size: 309x173mm (12.17x6.81") diag: 354mm (13.9") ratio: 16:9 modes: 1366x768
  API: OpenGL v: 4.6 Mesa 22.3.6 renderer: Mesa Intel UHD Graphics (ICL GT1) direct-render: Yes
Audio:
  Device-1: Intel Ice Lake-LP Smart Sound Audio vendor: ASUSTeK driver: snd_hda_intel v: kernel
    alternate: snd_sof_pci_intel_icl bus-ID: 00:1f.3 chip-ID: 8086:34c8 class-ID: 0403
  API: ALSA v: k6.1.0-13-amd64 status: kernel-api tools: alsamixer,amixer
  Server-1: PipeWire v: 0.3.65 status: active with: 1: pipewire-pulse status: active
    2: wireplumber status: active 3: pipewire-alsa type: plugin 4: pw-jack type: plugin
    tools: pactl,pw-cat,pw-cli,wpctl
Network:
  Device-1: Realtek RTL8822CE 802.11ac PCIe Wireless Network Adapter vendor: Lite-On
    driver: rtw_8822ce v: N/A modules: rtw88_8822ce,wl pcie: gen: 1 speed: 2.5 GT/s lanes: 1
    port: 3000 bus-ID: 01:00.0 chip-ID: 10ec:c822 class-ID: 0280
  IF: wlan0 state: up mac: <filter>
Bluetooth:
  Device-1: Lite-On Bluetooth Radio type: USB driver: btusb v: 0.8 bus-ID: 1-10:6
    chip-ID: 04ca:4005 class-ID: e001 serial: <filter>
  Report: hciconfig ID: hci0 rfk-id: 4 state: down bt-service: N/A rfk-block: hardware: no
    software: yes address: <filter>
  Info: acl-mtu: 1021:6 sco-mtu: 255:12 link-policy: rswitch hold sniff park
    link-mode: peripheral accept
RAID:
  Hardware-1: Intel 82801 Mobile SATA Controller [RAID mode] driver: ahci v: 3.0 port: 4060
    bus-ID: 00:17.0 chip-ID: 8086:282a rev: N/A class-ID: 0104
Drives:
  Local Storage: total: 908.71 GiB used: 348.24 GiB (38.3%)
  SMART Message: Unable to run smartctl. Root privileges required.
  ID-1: /dev/sda maj-min: 8:0 vendor: Samsung model: MZ7KM960HAHP-00005 size: 894.25 GiB
    block-size: physical: 512 B logical: 512 B speed: 6.0 Gb/s type: SSD serial: <filter> rev: 003Q
    scheme: GPT
  ID-2: /dev/sdb maj-min: 8:16 type: USB vendor: HP model: x796w size: 14.45 GiB block-size:
    physical: 512 B logical: 512 B type: N/A serial: <filter> rev: PMAP scheme: MBR
  SMART Message: Unknown USB bridge. Flash drive/Unsupported enclosure?
Partition:
  Message: No partition data found.
Swap:
  Kernel: swappiness: 15 (default 60) cache-pressure: 100 (default)
  ID-1: swap-1 type: partition size: 20.28 GiB used: 0 KiB (0.0%) priority: -2 dev: /dev/sda4
    maj-min: 8:4
Sensors:
  System Temperatures: cpu: 46.0 C mobo: N/A
  Fan Speeds (RPM): cpu: 1800
Repos:
  Packages: pm: dpkg pkgs: 2061 libs: 1043 tools: apt,apt-get,aptitude,nala,synaptic pm: rpm
    pkgs: 0 pm: flatpak pkgs: 0
  No active apt repos in: /etc/apt/sources.list
  Active apt repos in: /etc/apt/sources.list.d/debian-stable-updates.list
    1: deb http://deb.debian.org/debian bookworm-updates main contrib non-free non-free-firmware
  Active apt repos in: /etc/apt/sources.list.d/debian.list
    1: deb http://deb.debian.org/debian bookworm main contrib non-free non-free-firmware
    2: deb http://security.debian.org/debian-security bookworm-security main contrib non-free non-free-firmware
  Active apt repos in: /etc/apt/sources.list.d/mx.list
    1: deb http://mxrepo.com/mx/repo/ bookworm main non-free
Info:
  Processes: 276 Uptime: 9h 32m wakeups: 3 Memory: 19.34 GiB used: 3.32 GiB (17.2%) Init: SysVinit
  v: 3.06 runlevel: 5 default: graphical tool: systemctl Compilers: gcc: 12 Client: shell wrapper
  v: 5.2.15-release inxi: 3.3.26
Boot Mode: UEFI

Re: No more boot partition

Posted: Sun Nov 10, 2024 5:25 pm

by lachelp

To re-install a kernel I assume I would use "sudo apt install linux-kernel" or some such, but for the grub boot loader I am at a loss...

$ lsblk -f
NAME FSTYPE FSVER LABEL UUID FSAVAIL FSUSE% MOUNTPOINTS
loop0 squash 4.0 0 100% /live/linux
sda
├─sda1 vfat FAT32 FFDE-59EC
├─sda2 ext4 1.0 rootMX23 321710ba-00a7-4db7-a5ac-7aeb463b037b
├─sda3 ext4 1.0 home 051f82a5-739b-4a80-b27d-ff70700c8b24 236.4G 57% /media/demo/home
├─sda4 swap 1 35a87f30-e380-4357-91d8-44cd4e07f0f3 [SWAP]
└─sda5 vfat FAT32 SHARED C3D6-86A9
sdb
├─sdb1 exfat 1.0 Ventoy F9BA-8136
│ └─ventoy
│ 0 100% /live/boot-dev
└─sdb2 vfat FAT16 VTOYEFI F767-A619

demo@mx1:~
$ sudo parted --list
[sudo] password for demo:
Model: ATA SAMSUNG MZ7KM960 (scsi)
Disk /dev/sda: 960GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags:

Number Start End Size File system Name Flags
1 1049kB 316MB 315MB fat32 boot, esp
2 316MB 52.7GB 52.4GB ext4
3 52.7GB 726GB 673GB ext4
5 726GB 938GB 213GB fat32 msftdata
4 938GB 960GB 21.8GB linux-swap(v1) swap

Model: hp x796w (scsi)
Disk /dev/sdb: 15.5GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:

Number Start End Size Type File system Flags
1 1049kB 15.5GB 15.5GB primary boot
2 15.5GB 15.5GB 33.6MB primary fat16 esp

Model: Linux device-mapper (linear) (dm)
Disk /dev/mapper/ventoy: 2244MB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:

Number Start End Size Type File system Flags
2 633kB 9798kB 9165kB primary fat16 esp

fstab:
# /etc/fstab: static file system information
#
# Created by make-fstab on Sun Nov 10 07:42:51 EST 2024

# <file system> <mount point> <type> <options> <dump/pass>

# Added by make-fstab /dev/sda4
UUID=35a87f30-e380-4357-91d8-44cd4e07f0f3 swap swap defaults 0 0

Re: No more boot partition

Posted: Sun Nov 10, 2024 5:31 pm

by lachelp

Kermit the Frog wrote: ↑Sun Nov 10, 2024 8:43 am Till you post the QSI (as we don't know yet whether it's uefi or legacy etc..):

I wish you just run sudo update-grub on the other distro to make it detect MX ..

Roughly:
The /boot partition needs to be ext4 , not fat32

fat32 is for ESP (when it's uefi) , that also needs to have the flag(s) esp (and) boot ... (In fact the boot flag is needed by Windows, not Linux, we do it just by the way)

Thanks Kermit,

I have posted the QSI above but wanted to note that I could not have run sudo update-grub on the other distro as the other distro was BlissOS -- a fork of Android-X86, and it was not booting which is where the problem came from.

Also, the boot partition is ESP with flags esp (and) boot set.

Re: No more boot partition

Posted: Sun Nov 10, 2024 6:01 pm

by fehlix

lachelp wrote: ↑Sun Nov 10, 2024 5:25 pm To re-install a kernel I assume I would use "sudo apt install linux-kernel" or some such, but for the grub boot loader I am at a loss...

Better don't try anything until we got a clear picture of the situation.
Now, thanks for the commnand output.
Note: It is easier to read if you post those as code-block b/c all the formating is otherwsie lost:
So I take your text and wrapp here into those code-block marker: hit [</>] above the full post-edit to get the maker into the post.
lsblk -f

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NAME      FSTYPE FSVER LABEL    UUID                                 FSAVAIL FSUSE% MOUNTPOINTS
loop0     squash 4.0                                                       0   100% /live/linux
sda                                                                                 
├─sda1    vfat   FAT32          FFDE-59EC                                           
├─sda2    ext4   1.0   rootMX23 321710ba-00a7-4db7-a5ac-7aeb463b037b                
├─sda3    ext4   1.0   home     051f82a5-739b-4a80-b27d-ff70700c8b24  236.4G    57% /media/demo/home
├─sda4    swap   1              35a87f30-e380-4357-91d8-44cd4e07f0f3                [SWAP]
└─sda5    vfat   FAT32 SHARED   C3D6-86A9

so we only care about /dev/sda, not the ventoy USB-key.
and parted --list:

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Model: ATA SAMSUNG MZ7KM960 (scsi)
Disk /dev/sda: 960GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags: 

Number  Start   End     Size    File system     Name  Flags
 1      1049kB  316MB   315MB   fat32                 boot, esp
 2      316MB   52.7GB  52.4GB  ext4
 3      52.7GB  726GB   673GB   ext4
 5      726GB   938GB   213GB   fat32                 msftdata
 4      938GB   960GB   21.8GB  linux-swap(v1)        swap

This is the content of /etc/fstab: but from the running live system
fstab:

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# /etc/fstab: static file system information
#
# Created by make-fstab on Sun Nov 10 07:42:51 EST 2024

# <file system>                            <mount point>                               <type>     <options>                       <dump/pass>

# Added by make-fstab /dev/sda4
UUID=35a87f30-e380-4357-91d8-44cd4e07f0f3  swap                                        swap       defaults                        0 0

I was rather interested to see the fstab on the installed system on /dev/sda2 rootMX23.So you mount in thunar rootMX23
and post the ocntenent of /media/demo/rootMX23/etc/fstab
e.g on CLI (terminal commadn line)

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cat /media/demo/rootMX23/etc/fstab

Als you said in post nr #1

lachelp wrote: ↑Sun Nov 10, 2024 8:11 am My next step after multiple failed attempts to recover the old grub menu was to format the /boot partition

Are you saying you re-formatted "/dev/sda1"? Is this what you have done?
OK so please post fstab from the installed MX23 partition.
and in addition from the running Live systemn this:

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sudo efibootmgr -v

and again also a slightly modified command

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lsblk -f -o +PARTUUID

All nicely wrapped, please, within in code-block markers [code]text output goes here[/code]
Thanks

Re: No more boot partition

Posted: Sun Nov 10, 2024 6:15 pm

by lachelp

I was rather interested to see the fstab on the installed system on /dev/sda2 rootMX23.So you mount in thunar rootMX23
and post the ocntenent of /media/demo/rootMX23/etc/fstab
e.g on CLI (terminal commadn line)

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cat /media/demo/rootMX23/etc/fstab

Als you said in post nr #1

lachelp wrote: ↑Sun Nov 10, 2024 9:11 pm
My next step after multiple failed attempts to recover the old grub menu was to format the /boot partition

Are you saying you re-formatted "/dev/sda1"? Is this what you have done?
OK so please post fstab from the installed MX23 partition.
and in addition from the running Live systemn this:

Code: Select all
Code: Select all
sudo efibootmgr -v
and again also a slightly modified command

Code: Select all
Code: Select all
lsblk -f -o +PARTUUID
All nicely wrapped, please, within in code-block markers
Code: Select all
text output goes here
Thanks
Top

Oops, I see my error on the fstab I sent, here is the correct one:

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# Pluggable devices are handled by uDev, they are not in fstab
UUID=321710ba-00a7-4db7-a5ac-7aeb463b037b / ext4 discard,noatime 1 1
UUID=CDC3-E639 /boot/efi vfat noatime,dmask=0002,fmask=0113 0 0
UUID=051f82a5-739b-4a80-b27d-ff70700c8b24 /home ext4 noatime 1 2
UUID=35a87f30-e380-4357-91d8-44cd4e07f0f3 SWAP swap discard

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$ sudo efibootmgr -v
[sudo] password for demo:     
BootCurrent: 0002
Timeout: 1 seconds
BootOrder: 0002,0001
Boot0001* MX Linux	VenHw(99e275e7-75a0-4b37-a2e6-c5385e6c00cb)
Boot0002* UEFI: hp x796w PMAP, Partition 2	PciRoot(0x0)/Pci(0x14,0x0)/USB(1,0)/HD(2,MBR,0xf8c22cf4,0x1cd8000,0x10000)..BO

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$ lsblk -f -o +PARTUUID
NAME FSTYPE FSVER LABEL UUID                                 FSAVAIL FSUSE% MOUNTPOINTS PARTUUID
loop0
     squash 4.0                                                    0   100% /live/linux 
sda                                                                                     
├─sda1
│    vfat   FAT32       FFDE-59EC                                                       0ca53ab1-a841-40fa-8a00-91d0d7f57cee
├─sda2
│    ext4   1.0   rootMX23
│                       321710ba-00a7-4db7-a5ac-7aeb463b037b     26G    40% /media/demo/rootMX23
│                                                                                       1434acb3-d75b-49a5-bd68-a1f64e8d365b
├─sda3
│    ext4   1.0   home  051f82a5-739b-4a80-b27d-ff70700c8b24  236.4G    57% /media/demo/home
│                                                                                       b11ab444-5901-4c86-95da-dfc4e0245b15
├─sda4
│    swap   1           35a87f30-e380-4357-91d8-44cd4e07f0f3                [SWAP]      4422a9b6-002f-4c3e-bc36-61a84a218709
└─sda5
     vfat   FAT32 SHARED
                        C3D6-86A9                                                       6dacabae-7e15-4eb5-ab80-10ad3b067cb8
sdb                                                                                     
├─sdb1
│    exfat  1.0   Ventoy
│                       F9BA-8136                                                       f8c22cf4-01
│ └─ventoy
│                                                                  0   100% /live/boot-dev
│                                                                                       
└─sdb2
     vfat   FAT16 VTOYEFI
                        F767-A619                                                       f8c22cf4-02

HTH...

Re: No more boot partition

Posted: Sun Nov 10, 2024 6:34 pm

by fehlix

Can you change the fstab on the rootMX23
and change the 2nd line from

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UUID=CDC3-E639 /boot/efi vfat noatime,dmask=0002,fmask=0113 0 0

to

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UUID=FFDE-59EC /boot/efi vfat noatime,dmask=0002,fmask=0113 0 0

Next Chroot Rescue, from menu or open terminal as normal user and run

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sudo chroot-rescue-scan

select MX23 on sda2
if that works do run within chroot-terminal

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grub-install --force-extra-removable --target=x86_64-efi --bootloader-id=MX23 --recheck --efi-directory=/boot/efi

and

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update-grub

and also verify/confirm we have a new bootoption in NVRAM with

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efibootmgr -v

I think that's it. b/c "/Boot" as you posted was the esp not an extra /boot partition with a kernel on it.

Re: No more boot partition

Posted: Sun Nov 10, 2024 7:47 pm

by lachelp

Holly Buzzfart fehlix!!

It worked! You're a freakin' genius and I thank you for your time!!

Re: No more boot partition

Posted: Mon Nov 11, 2024 2:09 am

by fehlix

lachelp wrote: ↑Sun Nov 10, 2024 7:47 pm It worked!

Glad you made it. Perhaps tidy up the NVRAM and remove the non-funtional boot entry
shown with "efibootmgr -v" as

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Boot0001* MX Linux	VenHw(99e275e7-75a0-4b37-a2e6-c5385e6c00cb)

and remove on CLI with

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sudo efibootmgr -v --delete-bootnum --bootnum 1

or with short options

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sudo efibootmgr -v -B -b 1

or using GUI do remove with "Manage UEFI Boot Options" found within the tool "MX Boot Options"

Re: No more boot partition

Posted: Mon Nov 11, 2024 8:27 am

by lachelp

Thanks fehlix,

I've remove the non=functional boot entry, but how do I go about tidying up the NVRAM?

Re: No more boot partition

Posted: Mon Nov 11, 2024 10:12 am

by fehlix

lachelp wrote: ↑Mon Nov 11, 2024 8:27 am Thanks fehlix,

I've remove the non=functional boot entry, but how do I go about tidying up the NVRAM?

efibootmgr can read and write entries stored into the UEFI-NVRAM storage.
So if you removed the entry with efibootmgr or with MX "Manage Uefi Boot Options" you already
sorted the NVRAM. Some UEFI-firmware interface allow directly to remove those orphaned boot options.
Some other UEFI-firmware tidy up those by themself overtime.

Re: No more boot partition

Posted: Mon Nov 11, 2024 6:34 pm

by lachelp

Thank you for that, I did check both ways but cannot find the entry for the BlissOS installation that I deleted. I do see one labelled simply "UEFI OS" as option 3 but I am assuming that is the 'failsafe' (IRC) MX boot option but none for the BlissOS which is the last option still. Am I being blind or is it hiding?

Re: No more boot partition

Posted: Tue Nov 12, 2024 3:20 am

by fehlix

lachelp wrote: ↑Mon Nov 11, 2024 6:34 pm Thank you for that, I did check both ways but cannot find the entry for the BlissOS installation that I deleted. I do see one labelled simply "UEFI OS" as option 3 but I am assuming that is the 'failsafe' (IRC) MX boot option but none for the BlissOS which is the last option still. Am I being blind or is it hiding?

I don't know what you see, so I cannot comment on that.
In case the entry is not listed with "efibootmgr -v", than this is not visible from Linux,
so you may try to remove the entry from with the UEFI firmaware software (aks as BIOS setup).
A "Fallback" entry os sometjhing else, thats's the entry sown with UEFI boot option
list to "boot from the drive", where UEFI would search for the first ESP found
and within the ESP the efi-bootloader /EFI/BOOT/BOOTx64.efi
In case of "MX Linux" or the way you have resetted/regenerated the MX23 boot option,
it will also create the entry /EFI/BOOT/BOOTx64.efi to be identical
to /EFI/MX23/grubx64.efi. Which means you can either select "MX23" or
the fallback bootentry (the drive or whatever the label is used may be "UEFI OS" maybe
something else like the vendor name of the drive.)