Murder is a powerful yet underutilized deployment system leveraging the speed and efficiency of BitTorrent. This new update explores how Murder facilitates rapid and scalable file distribution across vast server environments, from hundreds to tens of thousands, where traditional methods falter. This approach offers a robust solution for organizations struggling with the limitations of centralized distribution systems.

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introduction)

Murder, a term typically associated with a flock of crows, aptly describes the coordinated action of servers working together in this system. Originally developed at Twitter, Murder provides a decentralized approach to file distribution, significantly improving deployment speed and reliability. This in-depth guide will cover the inner workings of Murder, its configuration, usage with Capistrano, manual implementation, and a comprehensive task reference. Let’s dive into the world of efficient deployments with Murder.

Understanding the Mechanics of Murder

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Murder utilizes several key components inherent to the BitTorrent protocol:

• Torrent Tracker: This central server, launched via the murder_tracker.py script, facilitates communication between peers. While technically centralized, the interaction remains minimal, reducing overhead. For simplicity, tracker-less distribution (DHT) is not currently supported. The tracker acts as a mini-HTTP server hosting the /announce path, where BitTorrent clients update their status.

• Seeder: The seeder hosts the files designated for deployment. These files are placed within a directory from which a torrent is generated. Murder archives the directory into a .tgz file and creates a corresponding .torrent file, a small file containing hash information about the archive. This .torrent file informs peers about the content they are downloading. The tracker monitors active .torrent files. At the start of a transfer, the seeder becomes the primary source for peers to download initial pieces. Subsequently, these pieces are distributed amongst the network, minimizing reliance on the seeder.

• Peers: These are the servers receiving and distributing the files. After downloading the .tgz file, a peer continues seeding for a short period, mitigating hotspot effects on the seeder. This peer-to-peer sharing drastically accelerates the deployment process.

Murder mystery movies often depict intricate networks, similar to how Murder connects and utilizes its peers for efficient file distribution.

Configuration and Usage with Capistrano

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Integrating Murder with Capistrano streamlines the deployment process. The simplest approach is using it as a deploy strategy, setting :deploy_via to :murder. Murder mirrors Capistrano’s assumptions, treating all servers without :no_release => true as peers. By default, the first peer acts as both tracker and seeder. You can customize these roles by redefining tracker, seeder, and peer if, for instance, a dedicated tracker is desired.

All participating servers require Python and the associated Murder support files (including BitTornado). Upload these files using:

cap murder:distribute_files

These files typically reside in shared/murder within your application’s deploy directory. Modify this location using the remote_murder_path variable. For automated setup, include an after hook:

after 'deploy:setup', 'murder:distribute_files'

Prior to deployment, initiate the tracker:

cap murder:start_tracker

Automate this step with deployment hooks:

before 'murder:start_seeding', 'murder:start_tracker'
after 'murder:stop_seeding', 'murder:stop_tracker'

With these steps completed, deploy as usual:

cap deploy

Define murder in the context of this system as the efficient and rapid distribution of files across a network of servers.

Manual Usage of Murder (Without Capistrano)

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Murder can distribute files across servers without Capistrano. Create a Capfile, require Murder, and define roles manually:

require 'rubygems'
require 'murder'

set :remote_murder_path, '/opt/local/murder' # or another directory

role :peer, 'host1', 'host2', 'host3', 'host4', 'host5', 'host6', 'host7'
role :seeder, 'host1'
role :tracker, 'host1'

To distribute a directory:

1. Start the Tracker:

cap murder:start_tracker

2. Create a Torrent and Start Seeding:

scp -r ./files host1:~/files
cap murder:create_torrent tag="Deploy1" files_path="~/files"
cap murder:start_seeding tag="Deploy1"

3. Distribute the Torrent to Peers:

cap murder:peer tag="Deploy1" destination_path="/tmp"

4. Stop the Seeder and Tracker:

cap murder:stop_seeding tag="Deploy1"
cap murder:stop_tracker

Files will then be available on all peers in /tmp/Deploy1.

Comprehensive Task Reference

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A.Good.Girls.Guide.to.Murder may involve meticulous planning, but Murder simplifies the deployment process through well-defined tasks:

• distribute_files: Transfers compressed support files from ./dist to all servers, clearing the destination directory (remote_murder_path) beforehand.

• start_tracker: Launches the BitTorrent tracker on port 8998.

• stop_tracker: Terminates the tracker process.

• create_torrent: Creates a .torrent file (identified by the tag argument) from a compressed directory specified by files_path, excluding .git directories. The .torrent file is downloaded to /tmp/TAG.tgz.torrent.

• download_torrent: Retrieves a lost .torrent file from the seeder using the specified tag.

• start_seeding: Connects the seeder to the tracker and initiates seeding.

• stop_seeding: Halts the seeding process on the seeder.

• stop_all_seeding: Terminates all active seeding processes.

• peer: Instructs peers to download and distribute files. Upon completion, files are extracted to destination_path/TAG/*.

• stop_all_peering: Forcibly terminates all active peer processes.

How get away murder in software development? By using Murder, achieving rapid and seamless deployments without the hassle of traditional methods.

Configuration Reference and Variables

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configuration-reference-and-variables)

Murder offers a range of configurable variables to customize the deployment process:

• default_tag: (Not recommended) A default tag name, simplifying task execution but risking file overwriting.

• default_seeder_files_path: The default file path on the seeder.

• default_destination_path: The default destination path on peers.

• remote_murder_path: The path for Murder support files on each host.

• default_temp_path: The base path for temporary files (defaults to /tmp, overridable via the temp_path environment variable).

Roles in Murder Deployment System

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roles-in-murder-deployment-system)

Murder on the orient express 2017 involved a complex web of characters, much like the distinct roles within Murder:

• tracker: The host running the BitTorrent tracker.
• seeder: The host providing the files for distribution.
• peers: The hosts receiving and distributing the files.

Conclusion: Leveraging Murder for Efficient Deployments

Murder offers a compelling alternative to traditional deployment strategies. By harnessing the power of BitTorrent, it achieves rapid and scalable file distribution across large server environments. While initially developed for large-scale deployments, its principles can be applied to a variety of contexts. This detailed overview provides the necessary knowledge to implement and effectively utilize Murder, streamlining your deployment pipeline and optimizing resource utilization. Explore the potential of Murder and transform your deployment process today. Consider exploring Murder for your next project and experience the benefits of efficient, decentralized deployments.