x0nu11byt3

ELF Format Cheatsheet

Introduction

Executable and Linkable Format (ELF), is the default binary format on Linux-based systems.

Compilation

zserge

#define _GNU_SOURCE
#include <asm/bootparam.h>
#include <errno.h>
#include <fcntl.h>
#include <linux/kvm.h>
#include <linux/kvm_para.h>
#include <stdarg.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>

mcastelino

Overview

The goal of this document to cover all aspects of Kubernetes management, including how resources are expressed, constrained and accounted for. This started a way to ensure that alternate container runtime implementation like Kata containers will behave from a resource accounting and consumption point of view in the same manner as runc.

Location of the latest version of this document: https://gist.github.com/mcastelino/b8ce9a70b00ee56036dadd70ded53e9f

If you do not understand cgroups please refer to a quick primer at the bottom of this document. This will help you understand how the resource enforcement actually works.

Kubernetes Resource Management

bufadu

How to build a load balancer with BGP and ECMP using VyOS

According to this cloudflare blog article "Load Balancing without Load Balancers", we can build a rock-solid load balancer only using a router. All the magic comes from BGP and Equal-Cost Multi-Path routing.

In this howto, I will use bird as BGP router on linux instance (ie. servers).

Test environment

I use GNS3 with this architecture :

jkstill

Decoding the data in /proc/net/tcp:

Linux 5.x  /proc/net/tcp
Linux 6.x  /proc/PID/net/tcp

Given a socket:

$ ls -l  /proc/24784/fd/11
lrwx------ 1 jkstill dba 64 Dec  4 16:22 /proc/24784/fd/11 -> socket:[15907701]

austinmarton

/*
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 */

#include <arpa/inet.h>
#include <linux/if_packet.h>
#include <stdio.h>