Booting from the Installation DVD

I recently found myself unable to log in to my system due to an incorrect Xorg file (50-device.conf) which resulted in a tight infinite processor loop and a rapidly scrolling monitor display. The obvious solution was to boot Linux from the Installation CD, mount the hard-drive system partition, and delete the file. (Note, “boot Linux” in the “more…” menu options rather than “boot from the hard drive”.)

However this resulted in the same problem. It was as though the O/S booted from the DVD was using the display subsystem on the hard-drive instead of its own independent display software. The only solution to that was to completely reinstall & update the root partition.

The other issue is that the DVD offers a text field for boot options, but I couldn’t find any help regarding what they were or the correct format in which to specify them.

Can anyone shed light on the above?

The ability to boot Linux from a DVD or memory stick can be extremely useful. As well as the situation above, it can be used to rescue user files when the O/S has died and it can do that on both Linux & Windows systems.

David L.

To me, that sounds unlikely. I have never had that happen.

I’m wondering if you accidentally selected the option to boot from hard drive.

The other issue is that the DVD offers a text field for boot options, but I couldn’t find any help regarding what they were or the correct format in which to specify them.

Most of the options that you are likely to need can be set with function keys (listed at bottom of the page). The text field is for anything else you happen to know about. If you enter something that the system does not know about, it will just be ignored. It won’t prevent booting.

For repairs, you probably should boot the DVD to the rescue system, which is purely command line – no display problems.

Those function keys only show up on Legacy, but not with the UEFI installer. Not sure why that decision was made to drop them in the UEFI installer.

Right. But the field to add boot options also only shows up for legacy. So the OP was apparently using legacy booting.

Not sure why that decision was made to drop them in the UEFI installer.

Legacy booting for the DVD is using “syslinux”. And UEFI booting is using “grub2-efi”. So I guess the answer is that “syslinux” provides the flexibility to put these things on the boot screen, while “grub2-efi” doesn’t.

I’m sure I tried the “rescue” option, but I’ve just run it again and verified that it does indeed boot Linux from the DVD rather than the hard drive and pass control to the CLI. Maybe the monitor was put into an odd state… I’ll consign that to the unknowns basket.

The menu does show the function-key boot options, but “text” (F5) couldn’t be selected when booting Linux, even from the hard drive.

But my main grouch is the confusing menus.

I initially assumed the “boot Linux” option on the “more…” menu would simply boot from the DVD, and a kernel initially loads from the DVD as one would expect. But one next has to select “a system to boot” and the only option presented to me was the one on the hard drive /dev/sda2. This was followed by a request to select a kernel from the two on the hard drive.

Next a confusing message that “you may select an alternative device name for the system partition” was displayed with ten options. They include /dev/sda2 which is clear enough, but the rest are generated names from /dev/disk/by-id, by-path, by-uuid which are pretty much meaningless as they stand. The one missing is /dev/disk/by-label which would have immediately identified the DVD: “OpenSUSE-Leap-42.3-DVD-x86_64033”.

In retrospect I can see what’s probably intended here, but surely it could be made simpler so it’s more obvious when the pressure is on?

Is the step to select “a system to boot” redundant when it’s confusingly followed by the offer to “select an alternative device name for the system partition” which includes the first option anyway?

That in itself is badly worded IMO, surely the message should simply be to select an boot source? And could all the /dev/disk options include /dev/disk/by-label? Or am I completely on the wrong track?

David L.

I have not used that option for at least 10 years. But I think it is supposed to boot into the system that you installed on disk. It is sometimes useful when booting from hard drive is broken.

In any case, the new installer for Leap 15.0 is much changed from that. It probably brings a different way of confusing people.

There is an option to “boot from hard drive” on the initial menu so I assumed “boot Linux” on the “more…” menu would boot it from the DVD. It’s all a learning experience, and I’ll look forward to being confused all over again with Leap 15 (:-).

Thanks for your input!