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  • 1.  EX2300 Switch can't load 'kernel' after Reset- Stuck in constant boot cycle.

    Posted 01-23-2023 12:41
    Hello, can anyone please help?

    I recently tried to reset a EX2300 Switch back to default factory settings, and now it cannot load the 'kernel' and is stuck in a constant boot cycle.  I reset the switch by depressing the reset button on the front of the device while re-attaching the power.
    I was able to interrupt the boot cycle using Control "C", and tried the following options without success:

    • Booting in recovery mode
    • USB Boot - with recovery image

    I'm not sure I did the USB Boot part correctly, and maybe that's the reason it hasn't worked. I've tried several things using advice from the Juniper Site, but I'm no further forward.  I am currently presented with the following:

    => <INTERRUPT>
    => 
      Here, I can boot from the USB - "usbboot"
    If I enter "reboot", it takes me to another mode:


    loader> ?
    Available commands:
    boot boot a file or loaded kernel
    autoboot boot automatically after a delay
    help detailed help
    ? list commands
    show show variable(s)
    set set a variable
    unset unset a variable
    echo echo arguments
    read read input from the terminal
    more show contents of a file
    lsdev list all devices
    include read commands from a file
    ls list files
    load load a kernel or module
    load_geli load a geli key
    unload unload all modules
    lsmod list loaded modules
    install install software package
    heap show heap usage
    reboot reboot the system
    devinfo show U-Boot devices
    sysinfo show U-Boot system info
    ubenv show or import U-Boot env vars
    fdt flattened device tree handling
    loader>

    I think I am doing something wrong, which is probably easily fixable. 

    Thanks for any advice!




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    PAUL BURNS
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  • 2.  RE: EX2300 Switch can't load 'kernel' after Reset- Stuck in constant boot cycle.

    Posted 01-24-2023 14:10
    Had faced similar issue.
    install OS from the boot loader (via ftp).


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    JAWAD HUSSAIN
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    Original Message


  • 3.  RE: EX2300 Switch can't load 'kernel' after Reset- Stuck in constant boot cycle.

    Posted 18 days ago

    Hello!

    I have had to recover quite a few 2300 and 3400s from the loader> prompt. I recommend following Bryan Ward's guide in creating a recovery USB, then using Juniper support article KB33842 in selecting and booting from the recovery USB. This will usually solve most of my problems, but you can also switch from one partition to another in U-Boot/loader if you want to see if it is healthier.

    Creating a Juniper Recovery USB Drive, the Easy Way – Bryan Ward

    Fix Device is not booting up with 'can't load kernel' error on EX3400/EX2300 Devices


    Switching partitions on 2300/3400s:

    - Restart the switch and as it boots up and spam ctrl+c a couple times until you enter U-Boot designated by the => symbol.
    - Use the following commands to switch between partitions
        setenv loaderdev disk0 / setenv loaderdev disk1
        saveenv
        reset
    - Switching between partitions can also be done in loader>, but it uses different commands.
        lsdev
        set currdev="disk0p1" / set currdev="disk0p2"
        echo $currdev
        boot



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    PARKER TEASDALE
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    Original Message