Support

The answer is not a simple yes and no.

No, it can't be possible to push updates remotely. The reason is that since Joomla! 1.6 the updates are no longer just a bunch of files you can extract on the server. There is also an update PHP script and several SQL files which may have to run on each update.

Yes, I have a solution! It's called Admin Tools Professional ;) One of the features is the Joomla! Update Notification Email plugin. When a new version of Joomla! is available, it sends out an email to all Super Administrators of your site. It also includes a handy link. When you click on it, it automatically logs you in and begins the Joomla! update. The link is valid only for 24 hours and once you or any other Super Administrator click on your link, all of the update links are automatically expired (so that there's very little window of opportunity for a hacker to exploit the link in order to log into your site).

So, there you have it. You only need to spend 20 Euros (or less, you get a discount if you already have an AKEEBAPRO subscription) per year. Then you can install Admin Tools Professional on all of your sites.

You can do that for Joomla! 1.5 but not on 1.6 or later. Reason: on Joomla! 1.5 updating meant copying over new files. In Joomla! 1.6, 1.7 and 2.5 you have to copy over new files, run the PHP upgrade script and the SQL update scripts. Unfortunately, these last two have to run from inside your site, otherwise your site will remain in a broken state. Running them remotely is not possible, ergo creating a multi-site updater is not possible. Not to mention that the actual upgrade can not run reliably on the majority of servers remotely. I mean, if you have a big upgrade (e.g. 1.7.4 to 2.5.3) on a slow shared host which is using the FTP mode you can not perform the upgrade in a single page load; it fails. Therefore you would need to have FTP access, not just a web API, to perform the remote update (something that Realtyna Maintenance Suite never took into account). Trust me, it gets very complicated very fast.

If you want to support a SINGLE server environment using server-side scripts (like what CloudAccess.net is doing) then it's very easy. But if you want something which can be installed by the user and work on all server environments, sorry, you need a magician not a developer :)

You are wrong about that. The fact that there is a PHP and a SQL update script means that Going from one version of Joomla! to the next does not require a migration. E.g., going from 1.6 to 1.7 to 2.5 was very smooth, despite these being three very different versions. Your only obstacles had to do with third party components, not Joomla! itself. So, there you have it, the joomla core team was thinking about you when they implemented that feature.

That said, since you are managing your own servers and your own hundreds of sites, I bet you can spend the money required to hire developers to build an automatic updater.