Category Archives: Linux

When will Google update kernel in Chromebooks

In the light or latest vulnerabilities found in Intel, AMD and some ARM processors found by Google researchers, everybody has summoned to create and install patches and fixes.

As an owner of one ARM Chromebook  currently running Linux Kernel Ver. 3.14.0 (Chrome OS after all updates installed) I am not sure whether it is subject of Meltdown and Spectre vulnerabilities, but according to Kroah-Hartman one of the main Linux kernel maintainers:

“If you rely on any other kernel tree other than 4.4, 4.9, or 4.14 right now, and you do not have a distribution supporting you, you are out of luck. The lack of patches to resolve the Meltdown problem is so minor compared to the hundreds of other known exploits and bugs that your kernel version currently contains. You need to worry about that more than anything else at this moment, and get your systems up to date first. Also, go yell at the people who forced you to run an obsoleted and insecure kernel version, they are the ones that need to learn that doing so is a totally reckless act.” read more

Switching to Raspberry Pi 3

As my server was running on A20-OLinuXino-LIME board, it started to freeze. I thought it is software issue and after some update it will be fixed, but that didn’t happen. When freezes even blinking LED stops blink.

So I decided to try Raspberry PI and installed Raspbian OS. No SSD disk as before, all running on micro SD card.

I am playing wit Pis for a long time (my first one is Rpi 1 Model B still running my weather station on the balcony).

Here I am – my blog on Pi, so far so good, will see. read more

Ransomware and Munich

In the lights of recent worldwide ransom-ware attacks- Wikipedia to computers in Windows world, I am wondering what happens to the process of migrating back from Linux (LiMux) to MS Windows in Munich City Government. As you probably know they managed to switch 15,000 desktop PCs from Windows to Linux and running fine for more than 10 years. Some local politician decided to go back after an offer from Microsoft to switch to Windows 10. Coincidentally Microsoft’s head quarter moved to Munich around the same time. read more

My new Chromebook

I bought an ASUS Chromebook Flip 10.1″ Touchscreen Laptop (Quad Core, 4GB, 16GB eMMC) – Aluminum Chassis. I know it is like a dumb terminal (browser), but as a Linux fan my intention is to install Linux on it. Boy that thing is thin – love it.

  • With 10-finger touchscreen, ASUS Chromebook C100 can be flipped over from 0 to 360 degree, using it as a Chromebook, or a tablet.
  • Quad-Core ARM 1.8GHz processor with 4GB RAM, Wireless 802.11 A/C
  • Built with aluminum chassis, 10.1″ HD IPS Display 1280 x 800. HD Webcam
  • Run android apps

When start it Chrome OS comes in no time. You have a browser and all Android apps in your disposal. read more

3.5 inch Touch Screen Display For Raspberry Pi 3

Today Santa brought me a new 3.5″ display  for my Raspberry PI 3 and I am busy now installing it and making it to work. Mine came with a Protective Case + 3 x Heat sinks+ Touch Pen read more

Measuring Temperature and Humidity with Raspberry Pi

After I played with OLED display with Raspberry PI, the next logical step is to display more useful information on it.

DHT22_AM2302

I bought a sensor DHT22_AM2302 which is a Digital Temperature Humidity Sensor with serial interface.

The device measures both temperature and humidity and you get the values in single poll.

Connected GND to Rpi’s GND,

Vcc to Rpi GPIO- pin 2 and finally

Data to GPIO pin 8 (GPIO 14)

rpi_T_H

Little bit of coding in Python and using nice libraries written by Tony DiCola for Adafruit Industries and here is the result. read more

OLED display to Raspberry Pi

Today I played with an OLED Display. I bought it from Amazon for $14 which is 0.96 Inch I2C and SPI Serial 128 x 64. It needs only 4 wires to connect to Raspberry Pi. This display is a monochrome (blue) – hence the price.

 i2cdetect -y 1

Showed the display detected on the I2C bus

Couple of lines of code from GitHUB – show IP address and the time. Graphics also can be drawn – lines, circles, rectangles, ellipses etc. even displaying .png files.

oledoled_1

#!/usr/bin/env python # # !!! Needs psutil (+ dependencies) installing: # $ sudo apt-get install python-dev # $ sudo pip install psutil # import os import sys if os.name != 'posix': sys.exit('platform not supported') import psutil from datetime import datetime from oled.device import ssd1306, sh1106 from oled.render import canvas from PIL import ImageDraw, ImageFont f = os.popen('/sbin/ifconfig wlan0 | grep "inet\ addr" | cut -d: -f2 | cut -d" " -f1') your_ip=f.read() from time import gmtime,localtime, strftime t = strftime("%Y-%m-%d %H:%M:%S", localtime()) def stats(oled): font = ImageFont.load_default() font3 = ImageFont.truetype('/root/oled/fonts/C&C Red Alert [INET].ttf', 18) font4 = ImageFont.truetype('/root/oled/fonts/C&C Red Alert [INET].ttf', 22) with canvas(oled) as draw: draw.text((0, 26), your_ip, font=font4, fill=255) draw.text((0, 48), t, font=font3, fill=255) def main(): oled = ssd1306(port=1, address=0x3C) stats(oled) if __name__ == "__main__": main() read more

Добавих твърдотелен диск към уеб сървъра

Купих си един твърдотелен диск (Solid State Disk SSD) ADATA 120GB за $45 и го добавих към сървъра с надеждата да се подобри производителността.

Кореновата файлова система я оставих на оригиналната SD карта,просто преместих /var директорията и swap файла върху новият диск. Да напомня, че MySQL, Apache, логовете и др. са във /var директорията. read more

Added Solid State Disk to the web server

Today I bought a Solid State Disk (SSD) ADATA 120GB for $45 and added it to the server in hope the performance will improve.

Root file system is still on the original SD card, I just moved /var directory and the swap file onto the new disk. Mind you that MySQL server, Apache web server, log files etc. are in /var directory.

First I created partition table and partitions with cfdisk. Next I formatted the partition with EXT4 file system, mounted the partition, added an entry in fstab.

Next I switched Linux to single user mode – server was connected to HDMI cable to the TV and USB keyboard (this can’t be done via ssh). Then I moved var folder onto the new partition and created symlink to the original place var should be. Rebooted and everything was back to normal. read more

Time-Lapse Video with Raspberry PI

I created time-lapse video with my Raspberry Pi. I used the Raspberry PI 5MP Camera Board Module (mine is NoIR version without IR filter). OS of choice is Raspbian. To avoid limits with SD card size, I mounted a share on my NFS server and generated the pictures there.
First testing the camera in single shot mode:

raspistill -o testimage.jpg

All was good, Then next step was to get picture every 16 seconds for 3hrs period and auto name them. read more