Various ways of running PHP 5.2 on Ubuntu 10.04 Lucid Lynx

The latest Long Term Support (LTS) release from Ubuntu has been with us for a bit over a month now, and I love it so far, on my laptop. This is Lucid Lynx 10.04, and will be supported until 2013 on the desktop, and more importantly, until 2015 on the server.

My servers are still on 8.04 though, the previous LTS, for good reason. 10.04 has PHP 5.3. While this is generally a better PHP, it has some compatibility issues with many Drupal, mainly for contributed modules, but some in core as well.

The long term solution to this is to find all PHP 5.3 compatibility issues and fix them in the code. This is a lengthy process though, and will not happen overnight.

So, in the meantime, there are several solutions for running PHP 5.2 on Lucid, some better than others.

In this post, we examine the different approaches, and the merits of each.

Approach 1: Installing Karmic's PHP 5.2 packages

The most common approach is to install Karmic 9.10's PHP 5.2 packages on 10.04. This has been reported to work for many, such as here, here and here.

The detailed instructions were originally posted here, and the following script is a refinement of that approach:

#!/bin/sh

# Script to install PHP 5.2 from 9.10 on 10.04
# And pin it so it does not get updated

PKGS=`dpkg -l | grep php | awk '{print $2}'`

apt-get remove $PKGS

sed s/lucid/karmic/g /etc/apt/sources.list | 
  tee /etc/apt/sources.list.d/karmic.list

mkdir -p /etc/apt/preferences.d/

for PACKAGE in $PKGS
do
  echo "Package: $PACKAGE
Pin: release a=karmic
Pin-Priority: 991
" | tee -a /etc/apt/preferences.d/php
done

apt-get update

apt-get install $PKGS

This is not the best solution though for many reasons, the main one is that these packages were compiled against libraries built for 9.10 and not 10.04. There is always a risk of unpredictable things happening when doing such a thing.

It also requires the packages to be "pinned" so no future security updates would be provided, unless 9.10 gets them too.

I also found no easy way to pin with aptitude, rather than with apt-get.

Approach 2: Proper PHP 5.2 packages, compiled for Lucid, installed manually

The fine folk at The Jibe took this one step further and built PHP 5.2 .deb packages for Lucid.

What this approach provides is that the packages are built against Lucid headers, and therefore solves the issue mentioned above.

What this solution suffers from is the lack of a repository. This means that the packages have to be downloaded and installed manually. Also, if you install them directly via the dpkg -i command, there may be unmet dependencies if you have not installed PHP 5.3 previously. This can be overcome by running the gdebi command instead, available in the "gdebi-core" package.

Still, the previous approach is too manual, and there is no way to check automatically for security updates for example.

Approach 3: Proper PHP 5.2 packages, compiled for Lucid, installed from a repository

So, the best solution, is to install from a repository
Ralph Janke's PHP 5.2 repository for Lucid

If you have the package "python-software-properties installed, you can easily add the repository using the command:

add-apt-repository ppa:txwikinger/php5.2

That will install the GPG key for security verification.

If you are using apt-get, then you need to create a file called /etc/apt/preferences.d/php for pinning the versions, so they remain at 5.2 and don't get upgraded to 5.3 when you run apt-get to upgrade your installation.

Put this in the file:

Package: libapache2-mod-php5
Pin: version 5.2.10*
Pin-Priority: 991

Package: libapache2-mod-php5filter
Pin: version 5.2.10*
Pin-Priority: 991

Package: php-pear
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-cgi
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-cli
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-common
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-curl
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-dbg
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-dev
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-gd
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-gmp
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-ldap
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-mhash
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-mysql
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-odbc
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-pgsql
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-pspell
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-recode
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-snmp
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-sqlite
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-sybase
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-tidy
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-xmlrpc
Pin: version 5.2.10*
Pin-Priority: 991

Package: php5-xsl
Pin: version 5.2.10*
Pin-Priority: 991

Then you do "apt-get update" and the right packages are either pulled in due to installing them directly or indirectly through dependencies.

That works fine for apt-get.

If you are using aptitude instead of apt-get, then skip the above pinning file, and tell aptitude to hold the version of PHP to what you have installed.

aptitude hold `dpkg -l | grep php | awk '{print $2}'`

Alternatively, you can do:

for PKG in `dpkg -l | grep php | awk '{print $2}'`
do
  echo "$PKG hold" | dpkg --set-selections
done

I am not sure if the above two commands are enough to stop aptitude from upgrading the packages to 5.3 if a new release comes by. If you find a better way to let aptitude handle this, please post it below.

Resources

Some further links that you may want to check:

• Slicehost forum post on the topic of PHP 5.2 downgrade, since PHP 5.3 breaks many applications, such as Drupal, MediaWiki and others.
• Another article on Lucid 10.04 for web development. Touches on the PHP downgrade topic.