Hi

I need some help for a big task I got to do soon.

We have a website since many year that is working with Joomla 1.5. This website has Multisite component installed and more than 300 slave sites.

The big question is : what is the simplest way to migrate all of these website to Joomla 2.5 ? Some components like JCE or Kunena forum are installed too.

For only one website, I used SP Ipgrade who makes a great job for this migration. But if I may have some help to know how to migrate 300 minisites, that would be great

Thanks a lot !

This is effectively a big task.

The tips is to use the SP Upgrade that allow "importing" a J1.5 website into a J2.5 website.

The SP Upgrade (at the difference with JUpgrade) can be executed from a slave site.
In fact the SP Upgrade, consider that you already have a Joomla (2.5 or 3.x) that is runing and that you import the data from another J1.5 website.

So you can repeate the operation for each slave site.

The approche of SP Upgrade is similar to the "Maintenance" menu present in JMS 1.3.
The difference is that SP Upgrade is based on the extension to import and migrate the data.
In JMS 1.3 maintenance, the approche is based on the MySQL table structure that can be adapted on a new structure. In fact JMS 1.3, try convert the existing DB structure (J1.5) into a new DB structure. It is destructive at the difference with SP Upgrade that work on another Joomla website and import (migrate) the Data.
The JMS "maintenance" can be used in addition to the SP Upgrade because SP Upgrade can not be execute iterativelly to fix some potential issues. The JMS "maintenance" can be executed on any extension as long as its data model structure (SQL) can be found.

The difference with the JMS maintenance menu is that it run in Ajax and can be executed on 300 websites.
If you want to see it progress, we suggest that you use the "Firefox" browser.
We noticed that Chrome does not display anything until that all the ajax command are finished. So you could have a "blank" screen during a very long period of time (several minutes or hours) without seeing the ajax progess.

If you are sharig the Joomla users or other extension content between the website, I think it would be possible to keep you current J1.5 DB and switch to J2.5 DB.
The idea would be to drop all the links and rebuild them with the J2.5.
This assume that you are using Kunena and JCE extnsion that are already compatible with J2.5

If you are using specific Joomla users for each mini-site, just try using the JMS maintenance but perform a very good backup before runing it.
Remember that it is destructive and that you can not roll back (except with a restore of a backup).

Thanks for your time to answer.

I did not had time actually to focus on this problem. I let you know when I will work on this if I was successfull.