Recent content on Shyam Jos
Recently when I tried to update my Fedora laptop I got the below error message Error: Loading repository 'fedora' has failed After some debugging I found out that this is due to a corrupted repo cache, we can easily fix this error by clearing all repo caches by running the below command sudo dnf clean all If that doesn’t work, you can run dnf command with debug options to see more details…
I often get messages from colleagues and friends how I keep myself updated with DevOps/SRE related news and articles, So today I am going to disclose my secret sources 😉 . Here is a the list of my top newsletters related to DevOps and SRE Devops Weekly : A weekly slice of devops news brought to you by Gareth Rushgrove. SRE Weekly : SRE Weekly is a newsletter devoted to everything related to…
My name is Shyam Jos, I am a passionate DevOps Engineer from Kochi, India . I am a strong advocate of using Linux and Open-Source software, always looking for ways to improve my skills through continuous learning. I love creating simple programs to automate tasks and solve everyday problems. You can find my code on GitHub . I also love creaing hardware projects using development boards like…
One of our application running in kubernetes have a background job feature (which is a bad practice and against stateless architecture) and recently we noticed some of these background jobs were killed in midway due to pod scale-down done by horizontal pod autoscaler. Our assumption was Kubernetes will only terminate pods with less utilization but we were wrong! and its a random selection. In…
You might have noticed that command output of PreStop hook won’t appear in pod logs and only thing you can see is whether the PreStop hook command failed or not is by checking kubernetes events log. So how can we see the PreStop hook command output in pod logs? By default container engine only redirects the stdout/err of the main process (running with PID 1 ) to the logging driver. Since the…
As part of migrating applications from EC2 instance to kubernetes I was assigned with a task of containerizing a CodeIgniter application. once the application was containerized I noticed that the application logs were writing to a local file inside the container. so I thought this can be easily fixed by changing the logging path in CodeIgniter config file to php://stdout . But it was not that…
In this tutorial I will show you how to batch resize and compress images in Ubuntu or in any other Linux distros(debian,arch and fedora). ‘Convert’ command is a very powerful image manipulation utility which comes preinstalled in almost all Linux distributions (ubuntu,debian,arch and fedora) and it is a part of ImageMagick software suite. Check if convert command is available on your…
Yay! finally received my 2019 hacktoberfest swag
Yay! finally received my 2018 hacktoberfest swag
In this tutorial, I will show you a simple way to RIP DVD into a single file using FFmpeg command line tool in Linux. Install FFmpeg in Ubuntu/Debian/Linux Mint # sudo apt-get install ffmpeg Now copy contents of your DVD to local directory and cd into VIDEO_TS directory Note: If you want to RIP the DVD directly without copying it to the local directory first , then you need to modify last part of…
What Type of file system is used in EFI partition ? # EFI partition in Ubuntu is basically a FAT partition with label “EFI” How to create / restore an efi partition ? # Just reformat or create a normal FAT file system partition with a size of 512MB (can be any size) and label it as “EFI”, You can use fdisk command if you are comfortable with cli or you can use gparted tool…
In this tutorial I will show you how to reinstall grub2 bootloader on a ubuntu system with efi partition. Boot from a live usb/cd # Boot from the ubuntu live usb/cd and select the option “try ubuntu without installing” Check if EFI is enabled in bios # Enter below command in terminal\ [ -d /sys/firmware/efi ] && echo "EFI boot on HDD" || echo "Legacy boot on HDD" If you see “EFI…
I have created a very simple HTML email alert Template for Icinga 2 to replace the default boring text-based email alert. This template can be easily installed by replacing existing alert scripts inside /etc/icinga2/scripts. Update: I have replaced mail command with mutt due to an incompatibility of options among different Linux distributions. Also, I have added new color highlight feature for…
As usual I was so bored and wanted to build something cool on this weekend, So I ended up building an Arduino based Linux server monitoring solution for monitoring my Linux VPS. The idea was Simple, use an Arduino Ethernet module to make a get request to the php script hosted on the server and parse the response data (free -m,df -h,uptime) and display it on the LCD screen every one minute. And…
Some of the wifi routers (especially beetel models) provided by airtel broadband is paired with two SSIDs(Access point), One is an actual SSID for internet access and another one called MGMNT, which is used by airtel for maintenance / automatic configuration. The default key for MGMNT is 0987654321 , which is hard-coded into the router’s firmware and the stupidest part is there is no option…
We can easily update Raspberry pi firmware in raspbian by running the command rpi-update, But in kali linux we dont have rpi-update command by default. To install the rpi-update in kali, run the following command: sudo curl -L --output /usr/bin/rpi-update https://raw.githubusercontent.com/Hexxeh/rpi-update/master/rpi-update && sudo chmod +x /usr/bin/rpi-update Then, to update your rpi firmware,…
Follow below steps to install jekyll on fedora Install jekyll # sudo dnf install ruby-devel redhat-rpm-config jekyll Optional packages # sudo dnf group install "C Development Tools and Libraries" sudo dnf install rubygems-devel nodejs bundler
I have been experimenting with different DIY antennas for RTLSDR since 2013,Below is my review on different antennas I have tested so far. For decoding NOAA weather satellite Signals # Quadrifilar Helix (QFH) Antenna is the most recommended antenna for APT signal reception, But I was too lazy to build one. So i decided to make a ground plane antenna with coat hanger. In my opinion GP antenna is…
NOAA satellite is a series of weather satellites launched by NASA. It carries a suite of instruments that provides data for weather and climate predictions, everyday multiple NOAA weather satellites pass above us. Each NOAA weather satellite broadcasts an Automatic Picture Transmission (APT) signal (137MHZ), which contains a live weather image of our area. RTL-SDR dongle combined with a good…