intika

Linux NetFilter, IP Tables and Conntrack Diagrams

IPTABLES TABLES and CHAINS

IPTables has the following 4 built-in tables.

1) Filter Table

Filter is default table for iptables. So, if you don’t define you own table, you’ll be using filter table. Iptables’s filter table has the following built-in chains.

ABOUT

about:config settings to harden the Firefox browser. Privacy and performance enhancements.
To change these settings type 'about:config' in the url bar. Then search the setting you would like to change and modify the value. Some settings may break certain websites from functioning and rendering normally. Some settings may also make firefox unstable. I am not liable for any damages/loss of data.

Not all these changes are necessary and will be dependent upon your usage and hardware. Do some research on settings if you don't understand what they do. These settings are best combined with your standard privacy extensions (~~HTTPS Everywhere~~ No longer required: Enable HTTPS-Only Mode, NoScript/Request Policy, uBlock origin, agent spoofing, ~~Privacy Badger~~ etc), and all plugins set to "Ask To Activate".

Quick Paste Ipvlan L3 Instructions

Host #1

ip netns add ns1
ip link add link eth1 ipvl1 type ipvlan mode l3
ip link set dev ipvl1 netns ns1

ip netns exec ns1 bash

Revert the full commit

Sometimes you may want to undo a whole commit with all changes. Instead of going through all the changes manually, you can simply tell git to revert a commit, which does not even have to be the last one. Reverting a commit means to create a new commit that undoes all changes that were made in the bad commit. Just like above, the bad commit remains there, but it no longer affects the the current master and any future commits on top of it.

git revert {commit_id}

About History Rewriting

Delete the last commit

Deleting the last commit is the easiest case. Let's say we have a remote origin with branch master that currently points to commit dd61ab32. We want to remove the top commit. Translated to git terminology, we want to force the master branch of the origin remote repository to the parent of dd61ab32:

Usage

Save the two files below. I put them in '~/.scripts'
Modify the configuration in konsole-watcher.sh to your liking
Modify the location of konsole-watcher.sh in konsole-watcher-autostart.sh if you chose to put it somewhere besides ~/.scripts
Create the directory ~/.konsole (or other location you chose for the save file)
Create a symlink to konsole-watcher-autostart.sh in '~/.config/autostart-scripts
or open System Settings > Startup and Shutdown and add a script to the Script Files (it does the same thing as creating the symlink)
You might want to add a menu entry as well in case KDE autostart doesn't work for some reason

psql: FATAL: Peer authentication failed for user “postgres” (or any user)

The connection failed because by default psql connects over UNIX sockets using peer authentication, that requires the current UNIX user to have the same user name as psql. So you will have to create the UNIX user postgres and then login as postgres or use sudo -u postgres psql database-name for accessing the database (and psql should not ask for a password).

If you cannot or do not want to create the UNIX user, like if you just want to connect to your database for ad hoc queries, forcing a socket connection using psql --host=localhost --dbname=database-name --username=postgres (as pointed out by @meyerson answer) will solve your immediate problem.

But if you intend to force password authentication over Unix sockets instead of the peer method, try changing the following pg_hba.conf* line:

from

	body
	{
	margin-top: 1px;
	margin-right: 3px;
	margin-left: 2px;
	margin-bottom: 3px;
	background: #201F1F;
	color: white;
	font-family: Bookerly, Segoe UI, Palatino Linotype, Arial Unicode MS;
	}

	#!/bin/bash

	# === INFO ===
	# altnetworking.sh
	# Description: Run the specified application in a custom networking environment.
	# Uses cgroups to run process(es) in a network environment of your own choosing (within limits!)
	VERSION="0.1.0"
	# Author: John Clark
	# Requirements: Debian 8 Jessie (plus iptables 1.6 from unstable)
	#

	# UPDATED 17 February 2019
	# Redirect all HTTP traffic to HTTPS
	server {
	listen 80;
	listen [::]:80;
	server_name www.domain.com domain.com;
	return 301 https://$host$request_uri;
	}

	# SSL configuration

	#!/bin/bash
	### Install PHP 7.1 on OPenSUSE 42.2 64Bits
	### https://build.opensuse.org/package/view_file/devel:languages:php/php7/php7.spec?expand=1
	### https://www.howtoforge.com/tutorial/how-to-install-php-7-on-debian/
	### http://www.shaunfreeman.name/compiling-php-7-on-centos/



	zypper in openssl-devel
	zypper in gcc gcc-c++ libxml2-devel pkgconfig libbz2-devel curl-devel libwebp-devel