Kubuntu Disappears

[JoHubb]

I have been running a triple boot system successfully now for over 2 years.

In the evenings, I sometimes leave an application running by mistake.

Yesterday and today mornings, when I return to check my work, as soon as I touch the mouse cursor, Kubuntu disappears - I get a black screen with a large white cursor.

I have to do a soft reboot but this default to the Windows 10 OS, normally my default is ubuntu on the UEFI/BIOS.

Checking the BIOS shows that the usual ubuntu drive is not in the boot menu. I disconnected the drives and reconnected serially and re-booted until I found one with the missing ubuntu distro.

When I moved this to the top of the list and rebooted I got this on a black screen (I've selected the items I thought were most relevant):

[#]Busybox v1.27.2
initramfs with a cursor and message to use a help command.

Unexpected inconsistency. Run fsck manually.

The root filesystem on /dev/sda2 requires a manual fsck.
[/#]
As I am now far out of my depth, I am posting here in the hope that someone can help me sort this out.

Thanks!

[Don B. Cilly]

You could try fsck /dev/sda2 or, if it doesn't work, exec fsck /dev/sda2 from the busybox prompt.

Or, well, what is the third OS?
If you can boot it, and it's Linux, you can sudo fsck /dev/sda2 from it.

Or run it from a live DVD/USB.

[JoHubb]

Thanks. fsck /dev/sda2 didn't work in Mint. It told me to find and then install e2fsck.

But the busybox command worked! Seems I had a multitude of problems with INODE all requiring a y/n response.

So far so good. I have rebooted a couple of times straight into Ubuntu. Unlike a similar setup on another PC, the grub menu on this PC doesn't list the /dev for each OS. It's handy to have and I once must have known how to do it. Septuagenarians are allowed to forget the odd thing, I hope!

Thanks again, Don B. Cilly.

[jglen490]

fsck is found in /sbin, and that means running it with sudo. So try

sudo fsck /dev/sda2

and then come bask with the results.

[JoHubb]

Okay, jglen

[Don B. Cilly]

Well, I did write sudo

If you can boot it, and it's Linux, you can sudo fsck /dev/sda2 from it.
Or run it from a live DVD/USB.

And suggested you do it from the other OS or a live medium because... you can't run it on a mounted partition.
Still, if it ran from the recovery prompt, all is good... hopefully. Because in my (limited) experience when that happens, more often than not the disk is starting to have problems - and they usually get worse, not better.
It doesn't have to be the case, but... I would set it to check the disk at startup often.
And, you know, backup and all ;·)

[jglen490]

If /dev/sda2 is your Linux OS partition, you will have run that command from a Live Distro USB because the partition has to be unmounted to run fsck on it. I know you said that one of your three OSes in Windows 10, but if you have another Linux as your third, you could boot to that third distro and run fsck from there.

[JoHubb]

If /dev/sda2 is your Linux OS partition, you will have run that command from a Live Distro USB because the partition has to be unmounted to run fsck on it. I know you said that one of your three OSes in Windows 10, but if you have another Linux as your third, you could boot to that third distro and run fsck from there.

I ran sudo fsck /dev/sda2 in Linux Mint.
Here is a screenshot of the result.



So I followed Don B Cilly's advice and used the busybox command - which worked and got me going again.

I worry about that HDD although it has only notched up 5000h. I have backed up. How best to check it? And how best to make a clone?

EDIT. I found Don B Cilly's link for checking. Thanks.

[Don B. Cilly]

For cloning, I like clonezilla.
It has the advantage that it only copies used sectors. So if it's a relatively big disk with relatively little data...

Just remember that, as it also clones the disk's UUID (it clones everything) you'll have to disconnect the old disk before connecting the new one, or it will really confuse your boot.
If you want to keep your old disk... there's a way to do it, just ask.

Also consider that SSDs have become quite affordable, and they do make for quite a difference in performance.

[JoHubb]

I have a lot of LibreOffice stuff, jpgs, etc, for presentations which I use on my Kubuntu side of things. The OS and the data are on the same 1TB drive. I am already up to 400GB on this and as speed isn't too important I'll stick with a good quality platter-type replacement.

I'll investigate Clonezilla. It would be useful to keep the 'old' disk so if there is a, hopefully, fairly simple way to do it, I'm all ears!

[Don B. Cilly]

OK. so you want to keep the old cloned disk.
This will lead to a very messy boot situation.* But. Just keep the cover of the Guide in sight. (That is, don't panic).

First thing you have to do is change the UUID of one of the cloned disks. Gparted will allow you to do that, from a GUI. KDE partition editor won't.
So - if you don't have it - you apt get gparted and change it. From any other the OS than the disk is on.
But. That is not enough. You also have to match the UUIDs in /etc/fstab - of all OSs you want to boot/use.

To see the UUIDs of your partitions:
sudo blkid
Edit /etc/fstab ** and check that the partition UUIDs match what it says there.
That should fix it. If it doesn't... you have access to a helpful forum :·)

*Most likely, it will boot from the old disk instead of the new one while it's telling you it's booting from the new one.
** As you may know, from 18.04 onwards, you don't have to sudo*** anything to do that. Even if you don't have write permissions, it will ask for a password on saving.

*** "sudo" means "I sweat" in Spanish and Italian, and we find it quite appropriate

[JoHubb]

Thanks, Don.

I'm sure I could do this. But messing with UUIDs scares me! What if I just cloned a new disk drive from the old one and put the new disk away in a drawer? That way, if or when the old drive fails, I could just plug in the new cloned one with the same UUID and continue. Or have I missed something?

[Don B. Cilly]

That sounds like a perfectly reasonable solution.
Of course you'll lose any changes you make in the meantime, but that's easily dealt with.

In theory, substituting the cloned drive should just let you boot from the new drive as if nothing had changed at all.
In practice... also :·) but there's always the possibility that St. Gremmlin doesn't like you or your computer - I'm quite sure he doesn't like me nor mine - and he will find mysterious ways.
But I would count that as very low probability.

[JoHubb]

I currently run 18.04 LTS.

I know we are getting away from my O/P but what if I installed 19.10 on the new HDD or maybe KDE Neon? Could I then simply copy over the data partition from the old disk and have it work? I do not know how tightly data is bound to a particular version of a distro.

In my experience, St Gremmlin has a way of extracting money from me when things go belly up...

Thanks for you interest and advice. I am probably at the limit of the Mod's patience so, if needs be I will start a new thread.

[Don B. Cilly]

Well, if the "data" partition just contains your "LibreOffice stuff, jpgs, etc, for presentations" I don't see how that can be a problem.
If it is the root partition and the "data" is the system, then it definitely will be.

Doing a clean install of another system... it depends on your level of customisation.
If you install 19.10, and copy your current /home directory over to it, all your settings will be preserved.
Additional software - that doesn't come with the default installation - you will have to re-install. But you'll get your settings for it back once it is.

If you install Neon... I'm not sure restoring your /home will work too well. It might. The core system is the same as 18.04, but a lot of the Plasma stuff won't be.
Maybe someone here knows better.
But it's certainly easy to recover some settings - like browser bookmarks, passwords, etc. - from the old ones anyway.