USB x86 boots in UEFI, not Legacy Boot ! Dell E7450

  • Hi Folks,


    I have read all the related threads (over the last 3 days of my attempts) but haven't come across this problem that I discovered by trial and error.


    1. So LE 10.0 latest (and another related distro 10.1.1 and 10.0.9) just doesn't boot on my Dell E74560 laptop with the latest A24 (Jun'20) BIOS, in default Legacy Boot. A19 (Feb'18) had exactly the same behavior.


    The laptop always boots in Windows 10 on HDD as usual.


    On an older Dell PC, it just hangs at the Dell splash showing F2/F12 Settings/Boot menu.


    2. This is USB boot, not the HDD install which stage I never got to, trying with LE USB Creator, Rufus and Win32DiskImager. All the files that should be there show up properly in Windows File manager, and I was able to get into syslinux.cfg to edit "installer" to "run" etc.


    I tried various USB2.0 sticks with all the 3 USB3.0 laptop slots. No luck.

    Deleting the EFI /BOOT folder or its files for Legacy Boot made no difference.


    3. Interestingly another USB2.0 stick with Ubuntu Mate 20.04 via Universal USB Installer booted fine on the same laptop under Legacy Boot.


    4. However, when I switched to UEFI boot on my Dell E7450, LE 10.0 (and the other distro) booted right away, with the 5 sec menu for install, run or live selection appearing.


    It shows UEFI ROM Build 42:32:36.


    5. The problem: Unluckily the Dell E7450 in UEFI mode doesn't detect the hard drive, so no go !


    I tried all kinds of online fixes, no luck. E.g.,

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    This seems a common issue from googling, and Dell advises that one needs to reinstall Windows 10 after switching from Legacy Boot to UEFI first (looks like the OS was installed with Legacy Boot, hence this issue):


    https://www.dell.com/support/k…tall-os-under-legacy-mode


    I want to avoid the reinstall pain for the additional potential of getting into some other issues !


    So:

    Is there a way to configure the boot path in syslinux.cfg for Legacy Boot, which is the recommended BIOS anyway?


    Curiously while I always changed the default GPT to MBR under Rufus, I noticed that the USB label under UEFI was something like " Pci.Root..USB...HD(1, GPT...)"


    Any insights ?

    Edited 5 times, last by shippy ().

  • When the Dell heuristic is not accepting the disk layout in legacy boot mode no configuration change can help.


    If you succeed in creating an disk image that boot on the Dell into any linux boot loader (e.g syslinux or grub) LibreELEC can be manually added to it.

  • mglae


    So you are saying that if I am able to legacy boot my Ubuntu UUI stick, I should be able to add LE to it?


    Can you kindly outline steps?


    1. I checked Universal USB Installer, and it has no LE listing and the non-listed Linux OS option doesn't work...Don't know if YUMI like multi installers would help.


    2. There was a 2 year old thread about using OpenElec boot but the attachment has vanished.


    Is that method still valid, and how? This should be more relevant compared with #1.

    Edited 2 times, last by shippy ().

  • I've no knowledge about the structure of an Ubuntu UUI stick therefore I can't answer this question.

  • I've no knowledge about the structure of an Ubuntu UUI stick therefore I can't answer this question.

    How about that OpenELEC boot, or any other method?

    I assumed from your first comment that you were pointing to a known solution. :/

  • Which thread? My web search foo seem not to be good enough to find it.


    To shorten this thread I've created an empty legacy boot only image with DOS partitioning scheme. After creating the stick you have to copy the LINUX and SYSTEM files of the desired LE release.


    LibreELEC-Generic.x86_64-legacy.empty.img.gz.zip

    mglae,


    Many thanks... wanted to respond.


    Since last night, after burning the boot image (all 3 tools) the USB drive disappears from my Win File Manager, and I have been reformatting via diskpart and Disk Management to repeat the process without luck ! This is a common issue so far.


    Anyway I might be able to try out your empty boot distro with the System and Kernel files copied once the USB drive stick and contents become visible again ! I am also thinking of trying Plop Boot Manager.


    Re: earlier threads, here is one of them that talks about a solution in message #39 by OP, which I don't understand owing to translation.

    Also I did try the #24 solution and then sdb/sda 1/2 methods subsequently, but no luck. :cool:


  • RE: "USB drive disappears from my Win File Manager"


    That's common.

    To solve that, start "Disk Management" tool or search for "Create and format hard disk partitions" (Win10 / Win11) and assign a drive letter to the FAT32 partition of the drive.

    => Just my 5 cents...

    ..//Jocke.Sve

  • RE: "USB drive disappears from my Win File Manager"


    That's common.

    To solve that, start "Disk Management" tool or search for "Create and format hard disk partitions" (Win10 / Win11) and assign a drive letter to the FAT32 partition of the drive.

    Great thanks for the little magic trick !


    mglae,


    1. No luck with your boot method: this time the laptop just hangs at the Dell splash, much as with the old Dell PC case in OP.


    And yes, because I want to avoid any nasty surprise (e.g., HDD Windows wipeout), I have been editing the syslinux.cfg from DEFAULT installer to DEFAULT run; and also been typing run at the prompt, just to avoid installation ! Hopefully this makes no difference.


    2. I also tried Ventoy

    Usually with Rufus, LE USB Creator I get the error : cannot mount UUID=...

    With Ventoy, I get either above or new error: cannot mount /flash/SYSTEM


    3. Tried Plop Boot Manager 5.0 - Install to the hard disk MBR (Master Boot Record)


    With USB Plop install, it did nothing- just booted straight into Windows as usual.

    With Windows Plop install, I got the additional Plop Menu. Upon choosing USB (only one connected), it gave me an error: USB: No boot device found...


    Then I selected HDA from the Plop menu, and it allowed me to boot into Windows.


    4. Question: Can I type anything at the debug shell to troubleshoot ?

    Do I need to label my USB drive partitions in a certain way?


    The boot partition was auto labeled E: by Disk Management, and I see a USB drive LIBREELEC(E:) and a USB Drive (D:)

    LIBREELEC(E:) contains the original syslinux.cfg, and SYSTEM and KERNEL (copied.)

    USB Drive (D:) asks to be reformatted (ignored.)



    So Dell BIOS is proving nasty... ;(

    Edited 6 times, last by shippy: Merged a post created by shippy into this post. ().

  • Now I'm confused: do you have always seen the syslinux boot screen?


    4. Question: Can I type anything at the debug shell to troubleshoot ?

    In this case:

    Code
    ls -l /flash
    blkid
    mount
  • Now I'm confused: do you have always seen the syslinux boot screen?


    In this case:

    Code
    ls -l /flash
    blkid
    mount

    Hi again mglae,


    I appreciate your quick help !


    I get the debug shell once I first install Rufus Syslinux 6.0.4 Boot and then add the LE Kernel and System files; then of course do USB boot.


    On regular USB boot (Rufus/ Creator install of LE 10.0.0.img.gz MBR file), get booted straight into Windows.


    1. Looks similar to the #24 solution in RDan thread above.


    A. Found the problem, but how do I proceed ? (Not a dev, just a noob who can monkey type ;) )


    14.04 - Mount can't find device in /etc/fstab - Ask Ubuntu


    B. Will this be a permanent solution embedded in some config file, or will I have to do this manually every time at the debug shell?



    ---------

    $ ls -l /flash

    $ blkid

    # list of disks with Windows ntfs and one usb /dev/sdb1 vfat partitions.)

    $ mount /dev/sdb1

    $ mount: can't find /dev/sdb1 in /etc/fstab

    -------


    Btw, here are contents of my syslinux.cfg file:


    ----------

    SAY Wait for installer mode to start automatically in 5 seconds...

    SAY

    SAY Options

    SAY =======

    SAY installer: permanently install AlexELEC to HDD/SSD

    SAY live: boot AlexELEC using RAM for temporary storage

    SAY run: boot AlexELEC using this USB memory device for storage

    SAY

    DEFAULT run

    TIMEOUT 50

    PROMPT 1


    LABEL installer

    KERNEL /KERNEL

    APPEND boot=UUID=1706-4700 installer quiet systemd.debug_shell vga=current


    LABEL live

    KERNEL /KERNEL

    APPEND boot=UUID=1706-4700 live quiet vga=current


    LABEL run

    KERNEL /KERNEL

    APPEND boot=UUID=1706-4700 disk=UUID=0e5bb5fd-2d05-46a9-bc3c-e1e8c33da701 portable quiet

    ----------

  • Now the error message is different: "Could not mount UUID=1706..."


    syslinux.cfg must have matching UUIDs. Replace 1706-4700 with 0E96-8A79.


    But then you can only boot installer and live. For run the second ext4 partition (sdb2) is required.

  • Now the error message is different: "Could not mount UUID=1706..."


    syslinux.cfg must have matching UUIDs. Replace 1706-4700 with 0E96-8A79.


    But then you can only boot installer and live. For run the second ext4 partition (sdb2) is required.

    mglae,


    1. Great...will try, and report results.

    2. Does this mean I will have to do manual config every time there is a new install?

    These UUID# don't look like they stay same?

    3. On my current config ( Syslinux 6.0.4 boot showing fat32 in my 14.9 GB USB space, and copy over Kernel and System files), how do I add ext4 partition to enable run mode?


    I rather not install LE to PC HDD, and live of course is not going to persist data on USB !

  • 2. Does this mean I will have to do manual config every time there is a new install?

    It is the nature of UUIDs to be unique. :) So yes, with any new created file system.


    3. On my current config ( Syslinux 6.0.4 boot showing fat32 in my 14.9 GB USB space, and copy over Kernel and System files), how do I add ext4 partition to enable run mode?

    Shrink the fat32 partition and create an additional ext4 one. (Don't forget to replace the disk=UUID= in syslinux.cfg)


    I'm not aware of any Windows tool capable of doing this. Use e.g. gparted from any Linux distribution or Gparted Live.

  • mglae,


    Success, with live mode ! :D What a wild ride !


    1. So that means one cannot configure a mountpoint etc in the LE .img file before boot, obviating need for manual UUID discovery at debug shell at boot time?


    That is, mountpoint needs to be created in the LE.img file first by author in /etc/fstab, (or by user via ssh in bootable LE, then backed up) e.g., sdb1 could point to the first USB attached.

    Then in syslinux.cfg, boot=disk= /dev/sdb1.


    Why was the UUID incorrect in first place? Just a generic entry?


    2. Is it possible to create an .iso image for LE, from source for example?

    (I tried renaming LE.img to LE.iso and it ran in Rufus, but the results were the same, no boot.)


    Would this help with Legacy Boot problems without creating additional concerns ?

    Edited once, last by shippy ().

  • 1.) The randomly generated UUIDs can be read from any linux system and then stored in the syslinux.cfg. LE is not using /etc/fstab.


    boot=/dev/sdb1 disk=/dev/sdb2 is possible but not reliable because it depend on the disk initialization order. Another possibility is to use boot=LABEL=xxx disk=LABEL=yyy if the file system labels are defined.


    The UUID was not incorrect, it still pointed to the original file system of the copied syslinux.cfg


    2) No. ISO is read only.


    Boot problems are very rare, although reported from time to time.

  • Ok... appreciate your explanations. 😺


    1. So, can we define system labels and /etc/fstab in the LE.img ?


    Here the idea is to configure as above and make a shrunk backup copy as LE-new.img. Then use LE-new.img for booting PC.


    This should then work as long as there is only one USB stick attached to PC ?


    2. Or, is there a better way to define UUIDs such that copying LE Kernel and System files over to a working boot like Rufus Syslinux6.0.4 might still auto boot?


    My own 3-4 year experience with LE and those other distros, including for tv boxes, says that boot problems are quite common.


    Boot should get more attention from devs and there should be more donors ! 🙈

    • Official Post

    In LE /etc/fstab exists inside a read-only squashfs file so you cannot edit it (and there is no need to). The location of KERNEL/SYSTEM and the filesystem for /storage are specified in boot configuration boot= and disk= .. and everything else will be automounted to /var/media by udevil and will be named according to disk-labels.