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Ask HN: Why is GitHub not considered distributed?

• rdc12 12y ago
  GitHub is a code hosting provider, that happens to use git (which is distributed), but the service they provide is run centrally and hence when their infrastructure fails, the service in not available (searching, tickets etc)
  • sidcool 12y ago
    Thanks, rdc12! What would an ideal Git service provider be like? Are there distributed alternatives? Is GitLab distributed?
    • rdc12 12y ago
      Well ideal is subjective, GitLab appears to also be a centralized model, but with an option to self-host. For a distributed solution, with similar features and purpose. You would probably be looking at a federated model.
      • sytse 12y ago
        Most people self-host GitLab. We would love an option to federate http://feedback.gitlab.com/forums/176466-general/suggestions/5097708-implement-cross-server-federated-merge-requests http://feedback.gitlab.com/forums/176466-general/suggestions... merge requests welcome
• andrewchambers 12y ago
  Github is a central server, it is not distributed at all, things like issue tracking and the wiki won't work if the server goes down. Git on the otherhand, is distributed because the central server is not required for most git operations to work if you have alternate methods of sending patches to eachother. The fact that git works even when Github is down works in Github's favor really nicely and makes server outages less noticeable.
  • sidcool 12y ago
    Oh, that makes sense? Can we pull, push from different machines running git without a git server?
    • andrewchambers 12y ago
      Yes, if you or your friends make a local github repo public via ssh or http you can just do pulls from eachother directly.
      • sidcool 12y ago
        That's fantastic! I don't need GitHub or Atlassian Stash or GitLab then! Thanks, @andrewchambers
        • andrewchambers 12y ago
          Git was originally designed to be used this way, github came later and designed it's product on top of git.
    • andrewchambers 12y ago
      You can test this pretty easily by just running ssh on your own machine and doing git clone ssh://sidcool@localhost:/home/sidcool/myrepo
      • sidcool 12y ago
        Do I need to expose any SSH keys for that? (Sorry if a noob question, I am new to Mac (and Unix)). Thanks!
        • andrewchambers 12y ago
          Just give it a test and see what errors you get. You can even play with just cloning local repositories without ssh. "git clone /path/to/localrepo newclone". You should be able to push and pull between local git repo's on your system too. It will help to learn about setting up remotes too. "git remote add otherfolder /path/to/other/repo" "git pull otherfolder"
• brudgers 12y ago
  Github != Git There is a type mismatch. Github is a webservice with a RESTful API. Git is a tool for building distributed databases with an emphasis on availability rather than consistency. If you have a project under Git source control and the only version is on Github then the project uses a remote repository but is not distributed. If you have a local repository in addition to one on Github then your project is distributed and in the event of a network partition (for example if Github goes down or your ISP goes offline) then the Git database is still available because you have access to the local repository. Now suppose you have six developers on the project and each has a local repository and uses the repository on Github as a remote repository. If Github goes down, then the network is partitioned in a way that keeps the developers from seeing each other's work...though each developer still has their local repository available. The important point is that Git doesn't require a hub and spoke configuration. The six developers can each have access to the five repositories of the other developers plus Github. Though it could be a bit messy for systematic merging to achieve reasonable consistency, such a configuration would be robust in the face of partition. A perhaps more practical possibility is to have a nearby Git server as a remote repository as well as Github and perhaps another server out on the interwebs...say on AWS...to provide redundancy against partition. There are really two strong features of Github which Git facilitates. Internally, it provides a team with a remote backup. Externally, it provides an organization with content distribution. However Github's centralized nature [it even has the word "hub" in it] makes it something less than a content distribution network and when it goes down it serves to illuminate the reasons that large long running open source projects mirror their content.
  • sidcool 12y ago
    Thanks for the detailed explanation, @brudgers. It helped!