MohamedAlaa

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

andreyvit

tmux cheat sheet

(C-x means ctrl+x, M-x means alt+x)

Prefix key

The default prefix is C-b. If you (or your muscle memory) prefer C-a, you need to add this to ~/.tmux.conf:

remap prefix to Control + a

drmalex07

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:

ngsmrk

stats = Sidekiq::Stats.new

stats.queues

stats.enqueued

stats.processed

stats.failed

dupuy

Markdown and reStructuredText

GitHub supports several lightweight markup languages for documentation; the most popular ones (generally, not just at GitHub) are Markdown and reStructuredText. Markdown is sometimes considered easier to use, and is often preferred when the purpose is simply to generate HTML. On the other hand, reStructuredText is more extensible and powerful, with native support (not just embedded HTML) for tables, as well as things like automatic generation of tables of contents.

jshaw

Byobu Commands
==============

        byobu                              Screen manager


Level 0 Commands (Quick Start)
------------------------------

        <F2>                               Create a new window

sivel

Better SSH Authorized Keys Management

A seemingly common problem that people encounter is how to handle all of your users authorized_keys file.

People struggle over management, ensuring that users only have specific keys in the authorized_keys file or even a method for expiring keys. A centralized key management system could help provide all of this functionality with a little scripting.

One piece of functionality overlooked in OpenSSH is the AuthorizedKeysCommand configuration keyword. This configuration allows you to specify a command that will run during login to retrieve a users public key file from a remote source and perform validation just as if the authorized_keys file was local.

Here is an example directory structure for a set of users with SSH public keys that can be shared out via a web server:

FredEckert

/*
To test that the Linux framebuffer is set up correctly, and that the device permissions
are correct, use the program below which opens the frame buffer and draws a gradient-
filled red square:

retrieved from:
Testing the Linux Framebuffer for Qtopia Core (qt4-x11-4.2.2)

http://cep.xor.aps.anl.gov/software/qt4-x11-4.2.2/qtopiacore-testingframebuffer.html
*/

jaymcgavren

# Instead of loading all of Rails, load the
# particular Rails dependencies we need
require 'sqlite3'
require 'active_record'

# Set up a database that resides in RAM
ActiveRecord::Base.establish_connection(
  adapter: 'sqlite3',
  database: ':memory:'
)

db0sch

If your master.key has been compromised, you might want to regenerate it.

No key regeneration feature at the moment. We have to do it manually.

1. Copy content of original credentials rails credentials:show somewhere temporarily.
2. Remove config/master.key and config/credentials.yml.enc
3. Run EDITOR=vim rails credentials:edit in the terminal: This command will create a new master.key and credentials.yml.enc if they do not exist.
4. Paste the original credentials you copied (step 1) in the new credentials file (and save + quit vim)
5. Add and Commit the file config/credentials.yml.enc