Ruby on rails 无法连接到mLab'；带rails的MongoDB

我正在使用Heroku和mLab

我将我的应用程序设置为使用MongoDB的mLab

它在Heroku和我的本地计算机上都不起作用

我可以使用命令行访问数据库：

mongo "mongodb://usrname:pass@ds333238.mlab.com:33238/heroku_4blzdg47"

但是当我在

config/mongoid.yml

中使用rails时：

production:
  sessions:
    default:
      uri: mongodb://usrname:pass@ds333238.mlab.com:33238/heroku_4blzdg47

这将是错误：

  MOPED: Could not resolve IP for: ds333238.mlab.com:33238, delta is 0.019052, error class is #<Resolv::ResolvError: Resolv::ResolvError>, retries is 0. Node is <Moped::Node resolved_address=nil> runtime: n/a
  MOPED: Could not resolve IP for: ds333238.mlab.com:33238, delta is 0.038719, error class is #<Resolv::ResolvError: Resolv::ResolvError>, retries is 1. Node is <Moped::Node resolved_address=nil> runtime: n/a
  MOPED: Could not resolve IP for: ds333238.mlab.com:33238, delta is 0.054449, error class is #<Resolv::ResolvError: Resolv::ResolvError>, retries is 2. Node is <Moped::Node resolved_address=nil> runtime: n/a
  Rendered homes/new.html.erb within layouts/application (368.6ms)
Completed 500 Internal Server Error in 385ms

ActionView::Template::Error (Could not connect to a primary node for replica set #<Moped::Cluster:70222534873720 @seeds=[<Moped::Node resolved_address=nil>]>)

有什么问题吗

我的部分珍品是：

ruby '2.3.7'
gem 'rails', '4.1.16'
gem "mongoid", '4.0.0'

---

在我将Mongoid更新到5.2版后，它运行良好。您使用的是一个不再受支持的古老版本的Mongoid。听起来这是一个新的应用程序；如果是这样的话，您应该使用Mongoid 7，MongoDB的当前Ruby驱动程序，等等。感谢您的建议：）我试图在不更新的情况下运行它，因为整个应用程序都是旧的。我需要花点时间来更新它。在我将Mongoid更新到5.2版之后，它工作得很好！

ruby '2.3.7'
gem 'rails', '4.1.16'
gem "mongoid", '4.0.0'