Comment # 13 on bug 1177900 from Harish Karumuthil

(In reply to Fabian Vogt from comment #12)
> (In reply to Harish Karumuthil from comment #11)
> > I am facing this same issue now . I tested it on following Live images.
> > 
> > 1. openSUSE-Tumbleweed-GNOME-Live-x86_64-Snapshot20221210-Media.iso
> > 2. openSUSE-Tumbleweed-KDE-Live-x86_64-Snapshot20221210-Media.iso
> > 3. openSUSE-Tumbleweed-KDE-Live-x86_64-Snapshot20221209-Media.iso
> > 
> > ( Ie, first day, I tested with KDE live image, then next day, I tested wit
> > both KDE and Gnome Live image on multiple hardware & Virtualbox )
> > 
> > Boot fails because  `/dev/disk/by-UUID` and/or `/dev/disk/by-label`
> > directories does not exists at the time iso-scan hook
> 
> How did you boot the .isos? Note that you must not use ventoy, it breaks the
> image.

Thanks for letting me know about Ventoy. I was not aware about it and was not
using it.
I used normal Grub to boot the Live image. my grub conf is given below.
```
menuentry "Select openSUSE Tumbleweed KDE Live" {
    set
iso_path=/openSUSE-Tumbleweed-KDE-Live-x86_64-Snapshot20221210-Media.iso
    set cdlabel=openSUSE_Tumbleweed_KDE_Live
}
menuentry "Select openSUSE Tumbleweed GNOME Live" {
    set
iso_path=/openSUSE-Tumbleweed-GNOME-Live-x86_64-Snapshot20221210-Media.iso
    set cdlabel=openSUSE_Tumbleweed_GNOME_Live
}
menuentry "openSUSE Tumbleweed KDE Live" --class os --unrestricted {
    set isoboot=iso-scan/filename=${iso_path}
    search --file --set=root ${iso_path}
    loopback loop ${iso_path}
    #set root=(loop)
    #set gfxpayload=keep
    echo Loading kernel...
    $linux (loop)/boot/x86_64/loader/linux ${cmd_persistent}
${cmd_safegraphics} ${isoboot}  root=live:CDLABEL=${cdlabel} rd.live.image
systemd.show_status=yes
    echo Loading initrd...
    $initrd (loop)/boot/x86_64/loader/initrd
}
```


There is a mistake in my previous comment. /dev/disk/by-UUID directory actually
existed there. But it was not updating when new loopback device is added. 

During the boot, it dropped to an emergency shell. There I checked.
`losetup -a` was showing successful attachment of iso image to loopback device. 
but, its link was not present in the `/dev/disk/by-label` directoy.
Then I run `udevadm trigger` and everything was populated correctly.

Next time, 
1. I put break in initqueue `rd.break=initqueue` in kernel param and removed
iso-scan/filename
2. Manually setup loop devices and run udevadm trigger
3. Exit the shell

This way I was able to boot the live images.