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Phusion Passenger 4.0.4 released

By Hongli Lai on May 27th, 2013

Phusion Passenger is software that deploys Ruby and Python web apps, by integrating into Apache and Nginx and turning them into a fully-featured application server. It is very fast, stable and robust and thus used by the likes of New York Times, AirBnB, Symantec, Pixar, etc. It comes with many features that makes your life easier and your application perform better.

Phusion Passenger is under constant maintenance and development. Version 4.0.4 is a bugfix release.

Phusion Passenger also has an Enterprise version which comes with a wide array of additional features. By buying Phusion Passenger Enterprise you will directly sponsor the development of the open source version.

Recent changes

  • Fixed autodetection of noexec-mount /tmp directory. Fixes issue #850
    and issue #625.
  • Fixed a WSGI bug. wsgi.input was a file object opened in text mode,
    but should be opened in binary mode. Fixes issue #881.
  • Fixed a potential crash in Out-of-Band Work. Fixes issue #894.
  • Fixed a potential crash in rolling restarting, which only occurs if a
    process was also being spawned at the same time. Fixes issue #896.
  • [Apache] The RailsBaseURI and RackBaseURI directives have been unified.
    For a long time, RailsBaseURI told Phusion Passenger that the given
    sub-URI belongs to a Rails 2 application. Attempt to use this
    directive with Rails 3 or with Rack applications would result in an
    error. Because this confused users, RailsBaseURI and RackBaseURI
    have now been unified and can now be used interchangably. Phusion
    Passenger will automatically detect what kind of application it is.
    The Nginx version already worked like this. Fixes issue #882.
  • [Standalone] The Passenger Standalone temp directory and
    PassengerWatchdog server instance directory have been unified.
    PassengerWatchdog already automatically updates the timestamps of
    all files in its server instance directory every 6 hours to prevent
    /tmp cleaners from deleting the directory. Therefore this
    unification prevents the Passenger Standalone temp directory to be
    deleted by /tmp cleaners as well. Fixes issue #654.
  • [Standalone] types_hash_max_size has been increased from 1024 to 2048.
    This solves a problem that causes Nginx not to start on some
    platforms. Contributed by Jan-Willem Koelewijn.

Installing 4.0.4

Quick install/upgrade

Phusion Passenger Enterprise users can download the Enterprise version of 4.0.4 from the Customer Area.

Open source users can install the open source version of 4.0.4 with the following commands:

gem install passenger

You can also download the tarball at Google Code. We strongly encourage you to cryptographically verify files after downloading them.

In-depth instructions

In-depth installation and upgrade instructions can be found in the Installation section of the documentation. The documentation covers:

  • Detailed tarball installation instructions.
  • Detailed upgrade instructions.
  • Installation troubleshooting.
  • Installation through APT and YUM.

You can view the documentation online here:


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