Ubuntu Crash and Kernel Panic

One night the week of March 8, 2015, the icons on my Ubuntu 14.04 desktop, under a limited standard user session, spontaneously changed to show padlock symbols on top of the icons. Basically, such symbols typically mean that the logged in user account does not have permission to files. Well, I can assure you I did nothing to revoke my own standard user account’s access to the files on my desktop. Yet, there was reality in contrast to my assumptions about the durability of my system. I decided to reboot and the trouble really began.

Kernel Panic

When I clicked the menu choice to reboot, the screen dropped into a command-line esque environment showing me that Fresh Clam was having some problems and Apache2 was as well (no idea about Apache2 since I don’t run it, or it could have been the Apache run time some software used). Anyway, I thought that was odd. I entered some keystrokes to get a command prompt and issued a reboot command manually. When the system came back, I had my first ever Kernel Panic since I privately resumed using Linux, principally Ubuntu, in 2009.

Apparently, the Init process was having issues and some message about kernel sync. Anyway, I spent 4 hours researching the matter before I decided, staying up past 3 am just wasn’t a good idea. There is a better solution for such situations. It consists of having an excellent recent backup of all your data and then simply re-installing the system. I slacked off on my backup a bit and that is why 4 hours of investigation seemed appropriate.

I also thought this may be a good opportunity to explore Kernel recovery in Init process senarios but since I spent the last 3 days prior reading between the lines that the Init process is on its way out in the Linux world, I said, maybe never mind. I was still intrigued, but I needed sleep. I also wanted to be back up and running at least an hour after I woke up.

File Recovery

I recovered my files pretty easily, despite all sorts of encryption. That reminded me that if I could recover so easily, I may need some more security. Anyway, the only thing I lost for sure was the most recent revisions of my Google bookmarks. I lamented that, because I spent a good deal of time on reorganizing them. Sure, I thought to get the actual Bookmarks binary file that Chrome sets up. I got that file easy enough but a re-install of Chrome wasn’t going to read the data back in when I replaced the default file from the install. It may be an anti-tampering thing Chrome does.

What I learned is that I need a better way to backup that consists of an automatic push to particular usb flash drives or hard drives by detecting mount points and uuids or something. Takes time to set that up smoothly and I keep promising myself I will get around to that one day. Anyway, the interesting thing was the Kernel Panic.

On the other hand, my PNY memory chips may have simply had an issue. I was too tired to do an extensive RAM test. I simply took one of the modules out, rebooted and swapped them between reboots. I did get slightly different error messages, but I decided to forgo the idea of failed RAM or disk.

Broken Init

Who would have thought Init would break. News was that Ubuntu online was switching from Init to systemd. It was to occur around the same night I had the problem. There is no way their switch over had any affect on my standalone configuration of Ubuntu. Still, the timing is way too coincidental. I pulled no Apt updates and I was briefly online to check some news. A little while after I disconnected, my system was starting on its way to disruption.

Linux on systemd

I thought on this for about an hour or so and considered that if Ubuntu is switching over to systemd, there may be some turbulence with Ubuntu for a while. I was on Ubuntu LTS and it should have been isolated from such things, but my impression ran to the contrary. The systemd process has been around for many, many years and I decided to pour through the C source code for systemd to understand some of it. The way Intel writes C code is pretty interesting.

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