Upgrading huge number of Joomla sites

Question

Joomla 1.5 will reach the end of its life in a short term and many site are being upgrade to a 1.7 or 2.5 version. We are trying to figure out how we can upgrade our sites. Unfortunately the developers of Joomla, who are doing a great job, haven't kept backwards compatibility high on their requirementslist.

We know there are many resources describing how to migrate a Joomla site to version X from version 1.5. But in our company we have about 120 Joomla sites. With all the migration steps that have to be done to the templates, custom written code and the third party modules we use this would be a hell of a job to migrate. So we are looking into methods and techniques that would make our (upgrade) job easier.

I can't imagine we are the only one with this problem so I am looking for more information on migrating these sites on a large scale. We can't be the only one who are struggling with this.

To give some detail, for upgrading of the minor versions we used the Vendor branches technique which worked awesome. In short, in our SVN repository we have a folder containing the current Joomla release. In the same repository we have a folder containing our own Joomla version with some custom code adjustments. Every project is based on that custom version. With the use of version branching we could easily update all our projects to the latest Joomla version.

For the major upgrade this technique won't be suitable. For instance we expect that some projects won't be upgraded to the new Joomla version for compability issues.

A way to solve this for the 2.5 branch could be to create two new folders with the 2.5 release of Joomla and our own customized 2.5 version. Each migrated project then would be branched of the 2.5 customized version. The migration process would be tedious and for sure be a manual drill.

We are afraid that we have to do this for every major release of Joomla so this won't be a real solution.

A solution we are thinking of is using phar and composer to create the project. If we succesfully can create a joomla phar as library and put custom development in an other phar, upgrading should be as simple as replacing the phar. Third party modules should be put into a phar archive also for easy updating. If modules don't support this, we are going to phar it ourself.

Of course we know that Joomla has a new, integrated update mechanism. We are looking into this mechanism but doubt we can use it since we have some custom patches to core code or module functionality.

To summarize this post, we have two challenges we'd love to get some feedback of.

1. How would you sggest upgrading 120+ sites to the latest release of Joomla
2. How do you manage Joomla updates if you have a large number of Joomla sites to maintain

Answer 1

The bad news is that there is no automated upgrade path from Joomla 1.5 to 2.5, as the changes are so drastic that they are almost like night and day. The template changes are such that you may have to rewrite them from scratch. Do not forget that 2.5 does a number of things differently too so you may also face a learning curve.

My suggestion would be to have a tiered migration plan and only migrate the sites that you need to or can justify the costs of the migration as the components, modules and plugins you use.

When doing so you need to watch the release schedule which provides a Long Term Release every 18 months each of which will most probably break backward compatibility from the previous versions, so you will end up with sites at 1.5, 2.5, 3.x etc

Answer 2

I believe that phar can be used in order to distribute a new upgraded version - but it will not help you in the upgrade process itself.

My (painful) experience with a migration from 1.5 to 1.7 taught me that not only the code changes were dramatic but also the DB changes (structure!), ACL implementation etc etc. The template will probably be the least of your problems.

My question back to you is, why do you want to upgrade ALL the websites ? if a specific website needs tools/plugins that are available only on higher versions of Joomla then I guess it's a good enough reason. But to upgrade all the websites will be, like you anticipate, a project from hell...