Tag: linux

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Most Linux users know some systemd by now. There is systemd stop $someservice and systemd disable $someservice. If you think that’s all one has to know about systemd you’re missing out on a lof of features. That’s not the story for today tho.

Some services tend to come back even when disabled and stopped. Socket services come to mind. This is e.g. the case for rpcbind starting a portmapper service on tcp/111 that can be used for a DDoS reflection attack. There are various ways to deal with this from uninstall to firewalling or to mask this service. Since everbody on Linux gets to pick their own poision I decided to use mask to make sure this can simply no longer start without having to break dependencies by removing it or fiddle with the firewall:

systemctl stop rpcbind.service
systemctl mask rpcbind.service
Created symlink /etc/systemd/system/rpcbind.service → /dev/null.
systemctl daemon-reload

A masked service can not even be restarted manually any more. It’s dead in the water as long as this symlink exists.

Read more on this from Poettering himself:

http://0pointer.de/blog/projects/three-levels-of-off

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One of the things about I love most is it’s flexibility. This may astonish some but I am gaming on my Linux system for approximately 15 years by now. Situation for improved a lot lately but it was always possible to keep myself distracted 😉

So one of the games I just love to play is XCOM (UFO series). I don’t think I skipped any part and Terror From The Deep will always have a special place in my heart. Anyway, when XCOM was relaunched and eventually ported to Linux by Feral Interactive in 2014 I thought I couldn’t have been happier. Firaxis Games topped this in 2016 with XCOM2 and Feral Interactive once more got the job for the port.

Sadly with all the expansion sets it takes quite a toll on the required hardware. Huge fan of all sliders on maximum and see how it goes and while my box can mostly keep up I notice that I run out of RAM towards the end of the game fast and my machine starts swapping. I’ve 16GB RAM and this game eats it away like children their candy.

I’ve got additional 4GB of swap installed on slow spinning rust disks (legacy) so I notice the moment it starts swapping like hitting a wall. After another frustrated restart of the game I paused for a moment. I don’t know why this games needs so much RAM and frankly I don’t even care. Maybe I’m spoiled nowadays since stuff tends to “just work”.

So I decided to throw more power at it but RAM is expensive and I usually have enough of it for my daily work (or other games). I did get a decent SSD (Solid State Disk) recently tho so it’s to my rescue:

swapoff -a
fallocate -l 16G /games/swapfile
mkswap /games/swapfile
swapon /games/swapfile

…and that’s it. I stopped my previous slow swap partition(s), created a new swapfile of 16GB size on my SSD, formatted it as swap partition and activated it. Now I tabbed back into my game and enjoyed the rest of the evening. Let it swap. The SSD can keep up with it. Not minding a few more seconds during loading screens 😀 I’m considerung to add the activation sequence to my “gaming mode” script.

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2 Crucial Things Desktop Linux Must Do To Find A Larger Audience by Jason EvangelhoJason Evangelho (Forbes)
It's time for better marketing, and it's time to form Voltron.

My first thought after reading https://www.forbes.com/sites/jasonevangelho/2019/10/25/2-crucial-things-desktop-linux-must-do-to-find-a-larger-audience by @killyourfm@layer8.space is: Yeah, just like the . Same issue.

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Episode 6: Paid Distros and Linux Laptops by Jason EvangelhoJason Evangelho from Linux For Everyone
Do you feel locked in to buying a laptop from a 'Linux laptop' company? Would you pay for your favorite Linux distro? All this + a Discovery of the Week double dose, Liam's favorite new Linux game and more!

Latest in my podcast list: Linux For Everyone [EP6] is out for some days now and today I had the time to listen to it – thank you @KillYourFM ♥️

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tl,dr: `systemctl suspend`

Sometimes I let my pc play music at night. Spotify still didn’t manage to implement a sleep function (even gorram Audible has this – and chances are the app crashes way before anyway).

I usually use `shutdown -h 60` or similar. Suspend tho? That’s another story. Hint: “suspend” is a bash builtin and not what you’d expect 😉

Looks like this changed (again) from `pm-suspend` to… systemd:

> sleep 1h; systemctl suspend

No sudo. yw.

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Did you know `ncdu`? I’m using this for years to find out where all my precious disk space is lost. Unlike other solutions it works in a terminal and this way even on remote servers… or gorram mobile phones always short on anything.

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Today I found out that I can use my Sony Action cam as… webcam (under Linux) for e.g. streaming or view control 🙂 Not really officially supported. Manual says: Use our shiny Android App and ustream (costs). The trick is so set it into ‘multi camera mode’ to trick it into joining my regular wlan via WPS. Once it’s on my wlan I can easily discover it’s API Scheme and make use of the Sony Camera Remote API controlling it via… JSON 😀 Now it’s just a matter of pointing OBS Studio to it’s lifestream. E voila 😀 I can now even write my own App instead of using that gorram Android App 😀

Played with the API. Taking photos (and download), change various settings, camera mode or start/stop recording worked flawless. Some other stuff I tried, like accessing the storage, not so. Probably doing something wrong.

Disclaimer: That device accepts commands (or stream access) from anyone – there’s no access control. Sony o0

Update: To register as regular v4l2 device that can be accessed e.g. by a webbrowser one can make use of a v4l2-loopback device.