Ruby on Rails：权限被拒绝-“ 0.0.0.0”端口80（Errno :: EACCES）的bind（2）

Question

重现步骤

1. 我创建了数据库并进行了迁移。
2. 我运行了rails server 。

结果是：

[3957] Puma starting in cluster mode...
[3957] * Version 3.10.0 (ruby 2.5.1-p57), codename: Russell's Teapot
[3957] * Min threads: 5, max threads: 5
    [3957] * Environment: development
    [3957] * Process workers: 4
    [3957] * Preloading application
    [3957] * Listening on tcp://0.0.0.0:80
    Exiting
    Traceback (most recent call last):
            22: from bin/rails:4:in `<main>'
            21: from bin/rails:4:in `require'
            20: from /home/my_username/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/railties-5.2.0/lib/rails/commands.rb:18:in `<top (required)>'
            19: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/railties-5.2.0/lib/rails/command.rb:46:in `invoke'
            18: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/railties-5.2.0/lib/rails/command/base.rb:65:in `perform'
            17: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/thor-0.20.0/lib/thor.rb:387:in `dispatch'
            16: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/thor-0.20.0/lib/thor/invocation.rb:126:in `invoke_command'
            15: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/thor-0.20.0/lib/thor/command.rb:27:in `run'
            14: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/railties-5.2.0/lib/rails/commands/server/server_command.rb:142:in `perform'
            13: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/railties-5.2.0/lib/rails/commands/server/server_command.rb:142:in `tap'
            12: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/railties-5.2.0/lib/rails/commands/server/server_command.rb:147:in `block in perform'
            11: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/railties-5.2.0/lib/rails/commands/server/server_command.rb:53:in `start'
            10: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/rack-2.0.5/lib/rack/server.rb:297:in `start'
             9: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/puma-3.10.0/lib/rack/handler/puma.rb:69:in `run'
             8: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/puma-3.10.0/lib/puma/launcher.rb:183:in `run'
             7: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/puma-3.10.0/lib/puma/cluster.rb:397:in `run'
             6: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/puma-3.10.0/lib/puma/runner.rb:144:in `load_and_bind'
             5: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/puma-3.10.0/lib/puma/binder.rb:88:in `parse'
             4: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/puma-3.10.0/lib/puma/binder.rb:88:in `each'
             3: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/puma-3.10.0/lib/puma/binder.rb:105:in `block in parse'
             2: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/puma-3.10.0/lib/puma/binder.rb:270:in `add_tcp_listener'
             1: from /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/puma-3.10.0/lib/puma/binder.rb:270:in `new'
    /home/my_usernam/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/puma-3.10.0/lib/puma/binder.rb:270:in `initialize': Permission denied - bind(2) for "0.0.0.0" port 80 (Errno::EACCES) 

Answer 1

将puma配置为使用其他端口。

# config/puma.rb
port(ENV.fetch('PORT', 3000))

在生产中设置PORT=80 ，在本地开发中未unset PORT 。

Rails默认在端口3000上监听，您可能已更改了一些设置以使其在端口80上运行。 普通用户不能打开低于1024的端口。– meagar♦

Permission denied - bind(2) for "0.0.0.0" port 80 (Errno::EACCES) 

只有root可以绑定低于1024的端口。请勿以root用户身份运行本地开发服务器！ 而是将端口配置为1024以上。