How Core Update in WordPress 2.7 Works?

In recent days, there are more and more information about WordPress version 2.7 coming up. Especially about the automatic upgrade of WordPress.

You already know the update function for Plugins, which is very convenient. Now the same for your WordPress installation, one click and you are up to date.

Such a powerful and important function comes along with some questions and doubts of course.

WordPress 2.7 Core Update
WordPress 2.7 Core Update

It’s your own decision if you want to trust this function, but it’s more secure than the automatic update for Plugins, since the Plugins are provided by different authors without control by the WordPress team. The process of the automatic WordPress update is well thought out, which I will explain, so you can get a better picture of it and it makes your decision easier for you if you want to use it or you still update manually.

  • Your installation sends version and localization to and proofs if there is a newer version available. If there is a newer version, it sends back an address to the new available version. It also sends it in the correct language of your current installation. But right now, there is only the English version.
  • If there is a newer version, the files will be downloaded in system-temp.
  • Afterwards it creates a folder wp-content/upgrade/core
  • Now the file wp-admin/includes/update-core.php will be copied from the new download package into the current installation.
  • This new file will be used to start the function update_core().
  • The new version will be proved.
  • A file will be created in root for the maintain modus (.maintenance file). The file wp-settings.php checks that and avoid any access if this file exists. The visitor will just see a simple HTML page with a short message:

    Briefly unavailable for scheduled maintenance. Check back in a minute.

  • Because of this maintain modus no one can access any files and now all files are getting copied from the installation package to the current installation.
  • All unneeded files are going to be deleted.
  • ugrade.php contains the information, that the database can be upgraded now. You have to confirm the database update, so it is only possible after all new files are copied to the current installation.
  • wp-content/upgrade/core will be deleted after a successful update.
  • The same with .maintenance.
  • After that the frontend is available again and all upgrade steps are listed in your admin area. Where you can see where a problem occurred if your upgrade wasn’t successful.





2 responses to “How Core Update in WordPress 2.7 Works?”

  1. […] With this method you have an easy way to deactivate, but you have to do it again when the next update for WordPress is knocking on your door. That can be a torture, especially when the automatic update is coming along with WordPress 2.7 – How core update in WordPress 2.7 works. […]

  2. Raoul Pop Avatar

    Could you please let me know if there’s some resource out there that talks in detail about troubleshooting the core update or the prerequisite server settings? I can’t find any decent documentation on this, and can’t get it to work on my server. It keeps asking for my FTP credentials and I keep getting an “error connecting to server” message in spite of entering the right credentials.