I’m finding that more and more software developers are being quite inconsiderate and are making code that requires PHP 5.3. Since many server-based and long-term support distros are still on PHP 5.2, this can make things difficult quickly.

I’ll share how I upgraded one of my servers, but I do need to let you know about some specifics about my setup as your setup may be different and require different steps to upgrade.

When I started, my system ran CentOS 5.5 and PHP 5.2.16. Now it is running CentOS 5.6 and PHP 5.3.3.

You won’t be able to follow these steps without root access, so that is definitely a requirement. I’m also running Apache. You may be using a different web server, but if you don’t know what I’m talking about, you are running Apache. I assume that if you run a different server, you will know what to change in my steps.

Upgrade CentOS 5.5 to CentOS 5.6

I found that CentOS 5.6, released earlier this year, had package support for PHP 5.3. That made me very excited. I thought that all I needed to do was to upgrade my distro, and I would be done (I would later find that I was naïve).

Fortunately, upgrading CentOS is very easy. I simply ran the following command to spawn a huge amount of work for the server:

[user@server ~]$ sudo yum update
[sudo] password for user:
Loaded plugins: fastestmirror, priorities
Loading mirror speeds from cached hostfile
 * addons: mirrors.tummy.com
 * base: centos.mirror.lstn.net
 * epel: fedora-epel.mirror.lstn.net
 * extras: mirror.ubiquityservers.com
 * updates: mirror.steadfast.net
Setting up Update Process
Resolving Dependencies
--> Running transaction check
---> Package amtu.x86_64 0:1.0.6-2.el5 set to be updated
---> Package asciidoc.noarch 0:8.6.5-1.el5.rf set to be updated
---> Package audit.x86_64 0:1.7.18-2.el5 set to be updated

...

Install       5 Package(s)
Upgrade     208 Package(s)
Remove        2 Package(s)
Reinstall     0 Package(s)
Downgrade     0 Package(s)

Total download size: 309 M
Is this ok [y/N]: y
Downloading Packages:
(1/213): avahi-glib-0.6.16-10.el5_6.x86_64.rpm          |  15 kB     00:00
(2/213): avahi-glib-0.6.16-10.el5_6.i386.rpm            |  15 kB     00:00
(3/213): rng-utils-2.0-4.el5.x86_64.rpm                 |  17 kB     00:00

...

Complete!
[user@server ~]$ 

Notice the white “y” toward the bottom. Before it does anything, you must answer its question with a “y”. Just hitting enter will cancel the upgrade.

This will take between 5-30 minutes on average depending on the number of packages to be upgraded, the speed of your system, and your servers connection speed. So pop open a root beer and wait for everything to finish up.

Reboot the server

Since this should have installed a new kernel for your system, you will want to reboot so that this new kernel can be loaded.

Rebooting a server can be a scary thing. Make sure that you know how to contact your hosting company’s tech support in case there are any problems with connecting to the server after the reboot. Also make sure that you notify any people that may be upset about the reboot before you do it.

Upgrade PHP 5.2 to PHP 5.3

I booted up my system and found that my PHP version was not upgraded:

[user@server ~]$ php -v
PHP 5.2.11 (cli) (built: Jan 17 2011 01:47:19)
Copyright (c) 1997-2009 The PHP Group
Zend Engine v2.2.0, Copyright (c) 1998-2009 Zend Technologies

This version of CentOS took the odd step of having both PHP 5.2 and PHP 5.3 packages. The main packages are 5.2 while another set with modified names are 5.3. For instance, the PHP 5.2 main package is php while the PHP 5.3 one is php53.

I still have no idea why they decided to do things this way, but I guess it has to do with some software not supporting 5.3 properly yet.

Since I couldn’t just install the php53 packages as they would conflict with the php packages, I had to remove all the existing PHP packages and install the new ones. This meant that I had to take stock of exactly what packages I had to remove and replace.

I used the yum commands list command to quickly get this information:

[user@server ~]$ yum list installed | grep php | cut -d' ' -f1
php.x86_64
php-cli.x86_64
php-common.x86_64
php-devel.x86_64
php-gd.x86_64
php-mbstring.x86_64
php-mysql.x86_64
php-mcrypt.x86_64
php-pdo.x86_64
php-pear.noarch
php-pgsql.x86_64
php-xml.x86_64
php-xmlrpc.x86_64
[user@server ~]$ 

The | cut -d' ' -f1 part at the end is just some fanciness to show only the package name and not the extra cruft.

Next I checked to make sure that those packages were available for php53:

[user@server ~]$ yum search php53 | cut -d' ' -f1 | grep php
php53.x86_64
php53-bcmath.x86_64
php53-cli.x86_64
php53-common.x86_64
php53-dba.x86_64
php53-devel.x86_64
php53-gd.x86_64
php53-imap.x86_64
php53-intl.x86_64
php53-ldap.x86_64
php53-mbstring.x86_64
php53-mysql.x86_64
php53-odbc.x86_64
php53-pdo.x86_64
php53-pgsql.x86_64
php53-process.x86_64
php53-pspell.x86_64
php53-snmp.x86_64
php53-soap.x86_64
php53-xml.x86_64
php53-xmlrpc.x86_64
[use@server ~]$ 

I quickly noticed that neither php53-mcrypt.x86_64 nor php53-pear.noarch were available. I would have to install these manually.

First, I shut down the Apache server as I didn’t want people going to broken pages as I did these updates:

[user@server ~]$ sudo service httpd stop
Stopping httpd:                                            [  OK  ]
[user@server ~]$ 

Next, I remove the old PHP packages:

[user@server ~]$ sudo yum remove php php-cli php-common php-devel php-gd php-mbstring php-mysql php-mcrypt php-pdo php-pear php-pgsql php-xml php-xmlrpc
Loaded plugins: fastestmirror, priorities
Setting up Remove Process
Resolving Dependencies
--> Running transaction check
---> Package php.x86_64 0:5.2.16-jason.1 set to be erased

...

Remove        13 Package(s)
Reinstall     0 Package(s)
Downgrade     0 Package(s)

Is this ok [y/N]: y
Downloading Packages:
Running rpm_check_debug
Running Transaction Test

...

Complete!
[user@server ~]$ 

Finally, I installed the available replacement packages:

[user@server ~]$ sudo yum install php53 php53-cli php53-common php53-devel php53-gd php53-mbstring php53-mysql php53-pdo php53-pgsql php53-xml php53-xmlrpc
Loaded plugins: fastestmirror, priorities
Loading mirror speeds from cached hostfile
 * base: centos.mirror.lstn.net
 * epel: fedora-epel.mirror.lstn.net
 * extras: mirror.ubiquityservers.com
 * updates: mirror.steadfast.net
Setting up Install Process

...

Install       2 Package(s)
Upgrade       0 Package(s)

Total download size: 18.5 M
Is this ok [y/N]: y
Downloading Packages:

...

Complete!
[user@server ~]$ 

Now it’s time to get the other PHP elements that were not available as packages.

Install PHP mcrypt

The php53-mcrypt package wasn’t available, so we have to install it manually. The following steps will accomplish this.

We first need to install the development package for mcrypt:

[user@server ~]$ sudo yum install php53-devel libmcrypt-devel gcc
...

PHP’s mcrypt extension can be compiled and installed from the source code, so we need to download and unpackage the PHP 5.3.3 source. You can find a download link on the PHP releases page. I used wget to make the process a bit quicker:

[user@server ~]$ wget http://museum.php.net/php5/php-5.3.3.tar.gz
--2011-12-07 14:32:00--  http://museum.php.net/php5/php-5.3.3.tar.gz
Resolving museum.php.net... 67.23.255.166
Connecting to museum.php.net|67.23.255.166|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 13921529 (13M) [application/x-gzip]
Saving to: 'php-5.3.3.tar.gz'

100%[=================================================>] 13,921,529  2.04M/s   in 6.6s

2011-06-24 19:10:40 (2.00 MB/s) - `php-5.3.3.tar.gz' saved [13921529/13921529]

[user@server ~]$ tar xf php-5.3.3.tar.gz
[user@server ~]$ 

Now we need to compile and install the mcrypt extension:

[user@server ~]$ cd php-5.3.3/ext/mcrypt/
[user@server mcrypt]$ phpize
Configuring for:
PHP Api Version:         20090626
Zend Module Api No:      20090626
Zend Extension Api No:   220090626
[user@server mcrypt]$ aclocal
[user@server mcrypt]$ ./configure
checking for egrep... grep -E
checking for a sed that does not truncate output... /bin/sed
checking for cc... cc

...

checking how to hardcode library paths into programs... immediate
configure: creating ./config.status
config.status: creating config.h
[user@server mcrypt]$ make
....

Build complete.
Don't forget to run 'make test'.

[user@server mcrypt]$ make test

Build complete.
Don't forget to run 'make test'.

=====================================================================
PHP         : /usr/bin/php
PHP_SAPI    : cli
PHP_VERSION : 5.3.3
ZEND_VERSION: 2.3.0

...

Do you want to send this report now? [Yns]: y

Please enter your email address.
(Your address will be mangled so that it will not go out on any
mailinglist in plain text): user@example.com

Posting to qa.php.net /buildtest-process.php

Thank you for helping to make PHP better.
[user@server mcrypt]$ sudo make install
Installing shared extensions:     /usr/lib64/php/modules/
[user@server mcrypt]$ 

Now all we have to do is set up the mcrypt.ini file so that the mcrypt extension loads with PHP. This file needs to reside at /etc/php.d/mcrypt.ini.

[user@server mcrypt]$ echo -e "; Enable mcrypt extension module\nextension=mcrypt.so" | sudo tee /etc/php.d/mcrypt.ini
; Enable mcrypt extension module
extension=mcrypt.so
[user@server mcrypt]$ 

Restarting the Apache server will load our new changes. (Thanks to Michael DePetrillo for pointing out that I originally skipped documenting this step.)

[user@server mcrypt]$ sudo service apache2 restart
 * Restarting web server apache2
 ... waiting                                                      [ OK ]
[user@server mcrypt]$ 

Install PHP Pear

Finally, I need to install PHP Pear. If you haven’t used it, it is essentially a code repository tool for easily installing, upgrading, and managing hosted code. It is basically PHP’s version of Perl’s CPAN.

Installing this is fairly straightforward.

[user@server ~]$ wget http://pear.php.net/go-pear.phar
--2011-06-24 15:18:22--  http://pear.php.net/go-pear.phar
Resolving pear.php.net... 78.129.214.25
Connecting to pear.php.net|78.129.214.25|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 3680148 (3.5M) [application/octet-stream]
Saving to: `go-pear.phar'

100%[=================================================>] 3,680,148    523K/s   in 7.3s

2011-06-24 15:18:29 (491 KB/s) - `go-pear.phar' saved [3680148/3680148]

FINISHED --2011-06-24 15:18:29--
Downloaded: 1 files, 3.5M in 7.3s (491 KB/s)
[user@server ~]$ sudo php go-pear.phar

Below is a suggested file layout for your new PEAR installation.  To
change individual locations, type the number in front of the
directory.  Type 'all' to change all of them or simply press Enter to
accept these locations.

...

Beginning install...
PHP Warning:  date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Chicago' for 'CDT/-5.0/DST' instead in phar:///usr/src/go-pear.phar/PEAR/Registry.php on line 1012
PHP Warning:  date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Chicago' for 'CDT/-5.0/DST' instead in phar:///usr/src/go-pear.phar/PEAR/Registry.php on line 1012
PHP Warning:  date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Chicago' for 'CDT/-5.0/DST' instead in phar:///usr/src/go-pear.phar/PEAR/Registry.php on line 1012
PHP Warning:  date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/Chicago' for 'CDT/-5.0/DST' instead in phar:///usr/src/go-pear.phar/PEAR/Registry.php on line 1012
Configuration written to /etc/pear.conf...
Initialized registry...

...

PEAR: Optional feature gtk2installer available (PEAR's PHP-GTK2-based installer)
PEAR: To install optional features use "pear install pear/PEAR#featurename"

The 'pear' command is now at your service at /usr/bin/pear
[user@server ~]$ 

Notice that ugly mess about the date() function. It’s PHP 5.3-specific. I posted how to fix it here.

Final Thoughts

All in all, this was much more complex than I had anticipated. I can understand why the CentOS devs had decided to make a separate set of packages for PHP 5.3, but it really has made things difficult. I do have to warn you that many other packages will start to take issue with this setup as they will have dependency requirements for the php package which naturally conflicts with the php53. This leads me to think that they have done this in a way that the repo was not supposed to support as the dependencies should not break in this fashion.

Oh well. Nothing is perfect.