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Phusion Passenger 2.2.9 released

By Hongli Lai on January 8th, 2010

Phusion Passenger is an Apache and Nginx module for deploying Ruby on Rails web applications, and is mainly focused on ease of use and stability.

Recent changes

Phusion Passenger is under constant maintenance and development. We are pleased to announce Phusion Passenger version 2.2.9. This is a bug fix release.

Fixed compatibility with Rails 3.

Actually, previous Phusion Passenger releases were already compatible with Rails 3, depending on the spawn method that would be invoked. Here’s the story:

Since Phusion Passenger 2.2.8, when the file exists, Phusion Passenger will treat the app as a Rack app, not as a Rails app. This is in contrast to earlier versions which gave Rails detection more priority than Rack detection. Phusion Passenger loads Rack apps and Rails apps in different ways. The Rails loader was not compatible with Rails 3, which is what we’ve fixed in this release.

That said, a Rails 3 app would have worked out-of-the-box on Phusion Passenger 2.2.8 as well because Rails 3 apps include a file by default, causing Phusion Passenger 2.2.8 to use the Rack loader. Earlier versions of Phusion Passenger would just completely bail out because they’d use the Rails loader.

With 2.2.9 there are still some caveats:

  • Smart spawning (the mechanism with which REE’s 33% memory reduction is implemented) is *not* supported for Rack apps. This means that if you want to utilize smart spawning with Rails 3, then you should remove your file.
  • Rails 3 depends on Rack 1.1.0. You must have Rack 1.1.0 installed as a gem, even if you’ve bundled it with the gem bundler. This is because Phusion Passenger itself depends on Rack.

Both of these caveats are temporary. We have plans to solve both of these properly in the future.

What’s up with the Gem Bundler?

There has been some reports that Phusion Passenger is not compatible with Yehuda Katz’s gem bundler. This might have been true for an earlier version of the gem bundler, but the latest version seems to work fine. Please note that you need to insert the following snippet in config/preinitializer.rb, as instructed by the gem bundler’s README:

require "#{RAILS_ROOT}/vendor/gems/environment"

The Rails::Boot monkey patching code as posted here does not seem to be required anymore.

Fixed support for ActiveRecord subclasses that connect to another database.
ActiveRecord subclasses that connect to a database other than the default one did not have their connection correctly cleared after forking. This can result in weird errors along the lines of "Lost connection to MySQL server during query". Issue #429.
[Nginx] Fixed PCRE URL.
passenger-install-nginx-module downloads PCRE 7.8 if PCRE is not already installed. However PCRE 7.8 has been removed from their FTP server, so we’ve updated the URL to point to the latest version, 8.0.

How do I upgrade to 2.2.9?

Via a gem

Please install it with the following command:

gem install passenger

Next, run:


Or, if you’re an Nginx user:


Please don’t forget to copy & paste the Apache/Nginx config snippet that the installer gives you.

Via a native Linux package

John Leach from Brightbox has kindly provided an Ubuntu 8.04 package for Phusion Passenger. The package is available from the Brightbox repository which you can find at:

Add the following line to the Third Party Software Sources:

deb hardy main

(The simplest way to do that is to create a file in /etc/apt/sources.list.d/ containing the deb instruction, and then run ‘apt-get update’).

Once you’ve done this then you can install Phusion Passenger by running:

sudo apt-get install libapache2-mod-passenger


sudo apt-get install nginx-brightbox

(Note that John is currently packaging 2.2.9, so it might take a while before this release shows up in the apt repository.)


Phusion Passenger is provided to the community for free. If you like Phusion Passenger, please consider sending us a donation. Thank you!