I have a joomla 1.5.26 site and want to upgrade over to Joomla 3.0.1. Is that possible? If so, what are the steps? I am looking for an installer like JUpgrade to do this.
I realize that it is a 2 step process: a. Migrate from Joomla 1.5.26 to Joomla 2.5
b. Migrate from Joomla 2.5 to Joomla 3.0.1
Use JUpgrade for both the steps after backing up your files using Akeeba / XCloner component
Am I right or am I missing a step?
It is better to stick with Joomla 2.5 as it is recommended till 2014. Here is statement quoted by joomla .org
"Joomla 2.5 is the Long Term Support (LTS) version of Joomla. That means that it has already undergone many months of real-world testing. Joomla 2.5 is stable, tested and reliable. Joomla 2.5 is the version being used by Joomla.org."
As you already know, you have to upgrade to Joomla 2.5 first, then to 3.x
Once you have upgraded to Joomla 2.5, download the 2.5-3.0.1 Update Patch and upload to the root folder in your FTP and extract it.
Of course, take a backup of your site before uploading the patch.
This may be a huge step for your website. If I were you I would upgrade to 2.5.
Joomla! 3.0 is really a short time release and in a couple of months you will have to upgrade again to 3.1.
Joomla! 2.5 is the current stable version. I would recommend it!
Joomla! Download page also states:
- Joomla! 2.5.x (Recommended for most websites)
- 3.0.x (Recommended for developers and early adopters)
Also it would be a good idea to have a look at the Joomla! 3.0. FAQ
Whether to do 2.5 or 3 depends totally on whether you are migrating third party extensions that are Joomla 3 ready or not. If you are just using the core, Joomla 3 is a simple update from 2.5 except that you will need to update your template ... but the fact is the coming from 1.5 you need to change your template for either 2.5 or 3, so you might as well go to J3 instead of having to do it again. Personally, unless I needed extensions I would just do J3 for any new site since you will have 3 years of support and be mobile ready. One thing you'll find about 2.5 and forward is that you need many fewer extensions than in the past.
The biggest problem with migration from 1.5 is that 2.5+ requires the asset table to be correct and in some cases JUpdate still seems to make it incorrect (generally if you had a third party extension that was using the content table). If your table is a reasonable size you can do a visual scan and make sure it looks sane. There are some ways to fix broken assets but never do it directly. There's a commercial product called ACL Manager that has asset repair and I also have an application that will run simple repairs that you could try https://github.com/elinw/AssetFix.
来源：https://stackoverflow.com/questions/13015859/upgrade-migrate-from-joomla-1-5-26-to-joomla-3-0-1