Tag Archives: Linux

How To shrink Journal Log files

Sometimes Journal Log files can take up a lot of diskspace. Here is how to make a fast cleanup

Delete logfiles and shrink until 500 MB in total size

journalctl --vacuum-size=500M

You will get an result that look like this

This freed up a lot of diskspace, but it may not have giving you as much free space as you think, if your value that you wan’t to shrink to is to low then the command will adjust to the lowest possible value

Get the size of the Journal Logs

Now here is how to see the current Journal disk usage

journalctl --disk-usage

How to copy .img files to floppy with DD

If you are into retro computing and need to copy one of the old floppy .img disks to a diskette then it can be done with dd for unix/linux or by using the windows port of dd

My son learning to code Power Basic for DOS and switching floppies 😉

In my case i had 2 computeres with a floppy drive, one was a Windows XP machine and the other was a much older DOS computer without USB or network and i need to test FreeDOS and MS DOS 6.2 but i only had files like disk1.img downloaded from the internet and blank 1.44 floppy disks.

In my first attempt i tried to use a Windows program called winimage but it was not able to run on the old Windows XP, maybe it needed a servicepack or somthing else, so the fastest way was to find a simpler and faster solution and dd came in to my rescue.

here is How to copy a disk.img to floppy with dd

Unix/Linux

dd if=disk1.img of=/dev/fd0

Windows (DOS or CMD Console)

dd if=disk1.img of=\\?\Device\Floppy0

It can be downloaded at http://www.chrysocome.net/download

OR from my server https://www.pvangsgaard.com/download/dd-windows/

Raspberry Pi | how to disable swapping

If you wan’t to disable swapping on your raspberry pi to prevent fast weardown of you SD card or even if you are using a SSD to boot on via USB it can reduce your disks lifespan if you have swapping turned on and it’s default on.

Here is how to completely disable swapping on Raspberry Pi (raspberian)

sudo dphys-swapfile swapoff
sudo dphys-swapfile uninstall
sudo update-rc.d dphys-swapfile remove
apt purge dphys-swapfile

This is tested on my Raspberry Pi 3 with Raspberian 9 (Debian 9 based)

WARNING: this is only a good idea if you know that the server has enough ram for it’s tasks.

CS:GO | Linux | Playing against my 10 year old kid and losing

I have tested Steam on my old Lenovo T450 laptop that is my secondary machine, it’s running Linux Mint 19 Cinnamon Edition and is working great with Steam. I’m quite surprised that it was fast enough to Play CS:GO and in the same time being recording a full desktop session, but it worked out just fine. My hardware is Core 5i CPU, 8 GB RAM, Intel HD 5500 Grapichs card, 128 GB SSD harddisk. I used KaZam to record with, it came with Linux Mint.