AlexAtkinson

BASH

Brace Expansion

🗒️ +(...) is part of extended globs, you need to enable them explicitly with shopt -s extglob

🗒️ expansions support glob -NOT- regex

https://www.gnu.org/savannah-checkouts/gnu/bash/manual/bash.html#Shell-Expansions https://www.gnu.org/savannah-checkouts/gnu/bash/manual/bash.html#Pattern-Matching

AlexAtkinson

# ----------------------------------------------------------------------
# File:         check_failover_dhcp.ps1
# Description:  NRPE Nagios Check for Windows Server 2012 DHCP Failover Servers
#               https://exchange.nagios.org/directory/Plugins/Network-Protocols/DHCP-and-BOOTP/Windows-2012-DHCP-Failover-and-Scope-Health-Check/details
#
#   Checks:     Failover State
#               Failover Mode
#               Scope State of Each Scope
#               Scope Statistics (PercentInUse) of Each Scope
#

AlexAtkinson

Domain Names, DNS, and URLs for DevOps & Friends

Table of Contents

AlexAtkinson

Evernote Alternative - Obsidian

This is my free Evernote alternative.

Tech Stack

There are three components of this solution: the note taking app, cloud-sync utility, and the optional cloud storage.

NOTE: If you don't need more than 2GB of cloud storage, you can get away with simply putting the vault in Dropbox and accessing from all your devices. NO NEED FOR SYNCTHING. Otherwise, read on.

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The Nines

Availability is measured in nines. Here's the breakdown:

Availability %	Downtime/Y	DownTime/Mo	Downtime/w	Downtime/d	Class
55.5555555% ("nine fives")	162.33 d	13.53 d	74.92 h	10.67 h
90% ("one nine")	36.53 d	73.05 h	16.80 h	2.40 h	1
95% ("one nine five")	18.26 d	36.53 h	8.40 h	1.20 h
97%	10.96 d	21.92 h	5.04 h	43.20 m

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Introduction

This is not a reprint of the docs, but a collection of tips, tricks, and specific guidance for my own reference, and the development of others.

Using

Interactive Container

So long as your container has a CLI, you can access it by specifying 'interactive' and 'tty' (pseudo-tty).

AlexAtkinson

#!/usr/bin/env bash
# file_watch.sh
# ------------------------------------------------------------------------------
# Description:
#   Watches a file for changes.
#   Includes output on inode changes as that may be desirable in some scenarios.
#   NOTE: ... Just use inotifywait.
#
# Usage:
#   ./file_watch <path/to/file>

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#!/bin/env bash
# Checks if subdomain.$1 is registered.
# Iterates the 1000 most popular subdomains.
#   NOTE: Can be changed to 10000, or even 100000.
#
# Usage:
#   ./dnsSUBflyover.sh nike.com
#
# NOTE:
#   For more subdomains:

AlexAtkinson

Adding Images to GISTs - The Gist Way

This approach relies on images being public in secret gists so long as you have the url to them.

1. Create a secret gist called something like "Images for Gists".
2. Clone the gist:
   • SSH: git clone git@gist.github.com:<hash>.git
   • HTTPS: git clone https://gist.github.com/<hash>.git
   • CREDIT: https://gist.github.com/mroderick/1afdd71aa69f6b29601d335751a1a9be
3. Add images and push them. Note that gists repos do not support directories.

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Jira Workflow Examples

This GIST is here simply to demonstrate some workflows I've found helpful in guaranteeing a well-developed backlog for iteration teams. That said, workflows can be as simple or as complex as you need for your organization/project. At scale though, it's highly desirable to have a backlog as beautifully maintained as your products as their qualities are interdependent. And you'll see this point surface in retrospectives/feedback over time.

Structure

First off, DO NOT have workflows that looks like this: