Linux

installing containerd and getting a sole kubelet to create pods via CRI

kernel tracing to figure out a little mistake

how to use overlayfs and some analysis of its performance impact in certain situations

a dive into the mechanics of writing to /proc/pid/uid_gid when setting up user namespaces

exploring how tar deals with uid and gids when archiving and extracting under different types of users

a deep dive into the mechanism that allows sudo to work

a look into the translations performed under the hood

exploring what glibc is, what ISO C and POSIX covers, and why golang might use glibc for some standard libraries.

going from source code to a working linux on qemu

Lessons learned building Concourse workers for ARM - a visit to CGO cross compilation, and necessary modifications to the workers' runtime

A deep dive into what goes under the hood in the Linux kernel when you can the socket system call

Check out how you can use the proc filesystem to retrieve the kernel stack trace of a given process

Go through the internals of implementing ulimit, how prlimit works, as well as inspecting how the kernel limits the number of open files

Go through the reason why free and top show the host's memory instead of container memory.

Go through how we can use syscalls to list directory entries and at which point procfs responds to that.

Get to know what is under the hood of procfs - what Linux does when you interact with /proc

The challenge has been set - a month of blog posts around procfs!

Check out how to fetch and install bpftrace using Ansible

Getting from Golang's net package down to the Linux kernel methods invoked when UDP messages are sent.

Dmesg allows us to grasp what's going on under the hood when the kernel gets bad. Check out how dmesg is able to read kernel logs and show to the user.

Check out how to pipe a live packet capture from tcpdump into a Wireshark instance in MacOS

There's no need to lose the great features of a well set up Vim configuration when coding eBPF code.

Check out how to configure YouCompleteMe to have auto completion and source code navigation capabilities for the Linux source code.

Privileged services are not something you can have with a regular Docker Swarm cluster. Check out how to have privileged containers using Docker Swarm Mode

Installing docker has never been easier - add the apt repository and install it. What about running your own fork of it?

Writing a TCP server in C can teach many things. Check out how to implement a TCP server and understand some of the syscalls involved in the process.

A deep dive into how to make use of ptrace to inspect syscalls made by a tracee while they occur.

How to extend Swap space on Linux after you already set it