Craig M craig-m-unsw

Understanding the Memory Layout of Linux Executables

Required tools for playing around with memory:

hexdump
objdump
readelf
xxd
gcore

README

Services declared as oneshot are expected to take some action and exit immediatelly (thus, they are not really services, no running processes remain). A common pattern for these type of service is to be defined by a setup and a teardown action.

Let's create a example foo service that when started creates a file, and when stopped it deletes it.

Define setup/teardown actions

Create executable file /opt/foo/setup-foo.sh:

Linux Backup Solutions

I've been looking for the best Linux backup system, and also reading lots of HN comments.

Instead of putting pros and cons of every backup system I'll just list some deal-breakers which would disqualify them.

Also I would like that you, the HN community, would add more deal breakers for these or other backup systems if you know some more and at the same time, if you have data to disprove some of the deal-breakers listed here (benchmarks, info about something being true for older releases but is fixed on newer releases), please share it so that I can edit this list accordingly.

Amanda (comments by sammcj)

It has a lot of management overhead and that's a problem if you don't have time for a full time backup administrator.

Install Vagrant

sudo su
apt-get update && apt-get install -y libvirt-dev ruby-all-dev apparmor-utils
curl -O -L https://dl.bintray.com/mitchellh/vagrant/vagrant_1.6.5_x86_64.deb
dpkg -i vagrant_1.6.5_x86_64.deb 
aa-complain /usr/lib/libvirt/virt-aa-helper # workaround
exit

Install vagrant-kvm as user

Introduction

Everyone who runs OSSEC on a Unix system has a common problem: you want to follow and apply security udpates closely, but every time you patch, you get a flood of alerts. And this problem quickly grows: if a given package update would result in five alerts, that's fine if you only have one server. But if you have a hundred servers? Five hundred? Five thousand?

So, I've cobbled some stuff together to abuse the OSSEC's Active Response mechanism to not raise an alert when a package is upgraded properly. I've tried to emulate the workflow of a human administrator as closely as closely as possible, but there are definitely some areas that could be handled better -- see Caveats below.

Objectives

Any time I get an OSSEC alert, I'll do any number of things that generally fall into three categories:

Validation of automated change: make sure the file was supposed to be upgraded: check the auto-upgrade logs, verify the package that installed/upgraded the file, etc.
Validation of expected

Learning Computer Security

About This Guide

This is an opinionated guide to learning about computer security (independently of a university or training program), starting with the absolute basics (suitable for someone without any exposure to or knowledge of computer security) and moving into progressively more difficult subject matter.

It seems that most people don't realize how much information is actually available on the internet. People love to share (especially geeks) and everything you need to become well versed in computer security is already available to you (and mostly for free). However, sometimes knowing where to start is the hardest part - which is the problem that this guide is intended to address. Therefore, this guide can accuratley be described as a 'guide to guides', with additional recommendations on effective learning and execises, based on my own experiences.

Many of the free resources are the best resources and this guide focuses on them. It is intended to provided a comprehensive

_________ _____ _______________       _____
\_   ___ \\    \\___________   \____ / ____\     ~/.bash/cliref.md
/    \  \/|    | |   ||       _/ __ \  __\    copy/paste from whatisdb
\     \___|__  |_|_  ||    |   \  __/|_ |   http://pastebin.com/yGmGiDQX
 \________  /_____ \_||____|_  /____  /_|     [email protected]
 20160515 \/ 1527 \/         \/     \/

alias CLIRef.txt='curl -s "http://pastebin.com/raw/yGmGiDQX" | less -i'

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

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	Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/45.0.2454.85 Safari/537.36
	Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko
	Mozilla/5.0 (Windows NT 6.1; WOW64; rv:40.0) Gecko/20100101 Firefox/40.0
	Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/600.8.9 (KHTML, like Gecko) Version/8.0.8 Safari/600.8.9
	Mozilla/5.0 (iPad; CPU OS 8_4_1 like Mac OS X) AppleWebKit/600.1.4 (KHTML, like Gecko) Version/8.0 Mobile/12H321 Safari/600.1.4
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	Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/45.0.2454.85 Safari/537.36
	Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/42.0.2311.135 Safari/537.36 Edge/12.10240
	Mozilla/5.0 (Windows NT 6.3; WOW64; rv:40.0)

	# ansible_plugins/filter_plugins/extras.py
	def merge_dicts(value, dict1):
	# return a merged dict
	result = {}
	result = value
	result.update(dict1)
	return result

	def merge_lists_of_dicts(list1, list2):
	# return a merged list