Tag: systemd

Good Morning from my Robotics Lab! This is Shadow_8472, and today, I’m addressing an annoying trio of issues I’ve had with Derpy Chips since I installed PopOS on it. Let’s get started!

The Problems

I have a number for gripes to myself about Derpy. I frequently have to stare at an ugly, gray login screen for to a minute and a half before I can select a user account. Tabs sometimes crash in FireFox, but only while I’m using it. Discord sometimes blinks, and I lose any posts in progress – possibly representing minutes of work.

Additionally, my mother uses a separate account to play Among Us on Derpy, and I have my account set up with a left-handed mouse she can’t use easily. Unfortunately, Derpy tends to crash whenever I try switching users, so I’ve been using a full power cycle. And that means we need another long, featureless login screen before the actual login. Some day, I really want to figure out how to change a login screen. Aside from how long this one takes, I’d much rather use the KDE one over GNOME 3.

The Plan

Of the three issues I’m setting out to address, long login is the most reproducible. Fickle FireFox and Ditzy Discord happen often enough to make Derpy frustrating to use as a daily driver, but sporadically enough to resist debugging on-demand. So I am planning on spending up to the full week on Derpy ready to catch the errors when they happen.

Going off what I have to start with, I’m assuming my FireFox and Discord issues are related. Both use the Internet for their every function, and the glitching tends to happen at times when a packet is logically being received: for FireFox, when a page is either loading or reloading, and Discord when someone is typing or has sent a post. If I had to hazard a guess, I would have to say Lengthy Login is directly caused by my NFS being mounted in /etc/fstab, and I’m not sure if there’s anything to be done about it except working the surrounding issues.

For this week, I an reaching out to the the Engineer Man Discord and a Mattermost community I found for PopOS. I don’t know much about the latter, but I heard the PopOS dev team frequents that forum.

The Research

I started by posting about my issues. Help was super-slow, and I often got buried. I don’t remember any self research making any sense. Anyone helping me in the PopOS support chat seemed obsessed with getting me to address Blank Login first, even though it was the least annoying of my three chosen issues, if only other stuff didn’t bug out on me.

Someone gave me a journalctl command to check my logs, and I did so shortly after a target glitch. It came back with a segfault error of some kind. I added this to my help thread and humored them about disabling my NFS fstab lines.

RAM or Motherboard?

When researching further for myself, I came across a number of topics I didn’t understand. I didn’t make any progress until someone told me to try memtest86+. What a headache! I installed the package, but had to dip into GRUB settings so I could boot into the tool. Even then, it kept crashing whenever I tried to run it with more than one stick of RAM at a time, as in the whole thing froze within 8 seconds save for a blinking + sign as part of the title card.

I was hoping at this point it was just a matter of reseating RAM. Best case: something was in there and just needed to be cleaned off. Worst case: a slot on the motherboard might have gone bad, meaning repair might be one of tedious, expensive, or impossible.

I tried finding the manual of Derpy’s motherboard, but the closest was the one for my personal motherboard, a similar model. Both come with 4 slots of RAM: two blue, two black. I used the first blue slot to make sure each stick of RAM passed one minute of testing, followed by a full pass of testing, which typically took between 20 and 30 minutes. I wasn’t careful with keeping my RAM modules straight, in part because I helped clean my church while leaving a test running.

I identified the fourth stick from a previously tested one I’d mixed it up with by how it lit up the error counter, starting just past one minute in. I tried reseating it several times, with similar results: the same few bits would sometimes fail when either reading of writing. If I had more time, I would have a program note the failing addresses and see if they were the same each pass as they kept adding up.

Further testing on the motherboard involved putting a good stick of RAM into each slot. Three worked, but one of the black slots refused to boot, as did filling the other three slots. I landed with leaving one blue slot empty for a total of 12 out of 16 gigs of RAM.

NFS Automount with Systemd

I still want relatively easy access to the NAS from a cold boot. “Hard mount in fstab has quite a few downsides…” cocopop of the PopOS help thread advised me. Using the right options helps, but ‘autofs’ was preferred historically and systemd now has a feature called automounts. I thought I might as well give the latter a try. cocopop also linked a blog post On-Demand NFS and Samba Connections in Linux with Systemd Automount.

I won’t go into the details here, but I highly recommend the above linked blog. It didn’t make sense at first, but after leaving it for a day, my earlier experiences with fstab translated to this new method within the span of about an hour total. I missed an instruction where I was supposed to enable automounting once configured, but it felt almost trivial.

Results

I haven’t had any problems with Discord or FireFox since setting the defective RAM aside in the anti-static bag it came in. As a bonus, switching users works correctly now as well.

NFS mounting is now much more streamlined with systemd. While I cannot say which method would have been more challenging to learn first, the tutorial I was following made this new method feel way more intuitive, even if file locations were less obvious. I didn’t even need any funny business with escape characters or special codes denoting a space in a file share name.

Takeaway

It really should go without mention that people will only help each other with what they know. I find myself answering rookie questions all the time when I’m after help with a more difficult one. Working side by side this week on a future topic, I had such a hard question, people kept coming in with easier questions, and I ended up asking mine enough times someone commented about the cyclic experience. The same thing kept happening with the easy part of my question about login.

Final Question

Do you ever find yourself asking a multi-part question, only to have everyone helping you with just the easiest parts you’ve almost figured out?