AtulKsol

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

itod

• Kinesis Freestyle (Terrible key switches. Mushy and un-lovable)

• Kinesis Freestyle Edge (Traditional layout with too many keys, mech switches, proably too big to be tented easily/properly)

• Matias Ergo Pro (Looks pretty great. Have not tried.)

• ErgoDox Kit (Currently, my everyday keyboard. Can buy pre-assembled on eBay.)

• ErgoDox EZ (Prolly the best option for most people.)

mcastelino

The netfilter hooks in the kernel and where they hook in the packet flow

The figure below calls out

• The netfilter hooks
• The order of table traversal

ageis

security and hardening options for systemd service units

A common and reliable pattern in service unit files is thus:

NoNewPrivileges=yes
PrivateTmp=yes
PrivateDevices=yes
DevicePolicy=closed
ProtectSystem=strict

enjalot

Quick, Draw! ndjson data

The Quick, Draw! dataset uses ndjson as one of the formats to store its millions of drawings.

We can use the ndjons-cli utility to quickly create interesting subsets of this dataset.

The drawings (stroke data and associated metadata) are stored as one JSON object per line. e.g.:

{

trastle

global:
  scrape_interval: 60s

  external_labels:
    monitor: 'example'

rule_files:
  - /etc/prometheus/config/*.rules

scrape_configs:

galexrt

#!/bin/bash

version="${VERSION:-1.0.1}"
arch="${ARCH:-linux-amd64}"
bin_dir="${BIN_DIR:-/usr/local/bin}"

wget "https://github.com/prometheus/node_exporter/releases/download/v$version/node_exporter-$version.$arch.tar.gz" \
    -O /tmp/node_exporter.tar.gz

mkdir -p /tmp/node_exporter

rubencaro

Golang installation guide

Since Golang version 1.11 this process is finally (almost) as easy as it should (!!). You can see full docs here. For older guides see here.

These are my notes, not a generic solution. They are not meant to work anywhere outside my machines. Update version numbers to whatever are the current ones while you do this.

Installing everything needed the first time

Install asdf and its golang plugin, then install golang

DominicBreuker

iptables cheat sheet

Concepts

iptables defines tables, which group features:

• filter: use it to filter traffic
• nat: use it to implement NAT
• raw: use it to define which connections iptables should track (stateful firewall)
• mangle: use it to change some fields in packets (e.g., TTL)
• security: use it to define access control

jon-a-nygaard

A Highcharts example in use with Webpack and Babel.

Install

1. Download source files
2. Run npm install to install all dependencies.
3. Run npm run build to bundle app.js into bundle.js

Open application

1. Open index.html in a browser.