Just four years ago, I migrated my site from Drupal 7 to 8 and now I was forced to update to the new version, which is Drupal 9. Indeed the expiration date, the next November, is nearby, but above all I wanted to change my obsolete theme. Now it has a more modern and optimized look. Below I will describe my brief experience which fortunately was less complicated than expected.
Generally speaking, it is the opposite, because people need to port online their website after creating it in a private environment. But it happened in 2017 and I removed it from my computer after installing a new operating system. Recently I have discovered that the support of my Drupal 8 site will end in November 2, 2021 and I have a lot of incompatibilities with Drupal 9x. So I have to fix them in order to migrate to the new main release of Drupal.
The 2017 has just begun and I wish to tell again my adventures in programming and my IT passions in general. It is an ambition because my job is very heavy and gives me little time left. But like an Italian idiom that says "There's no harm in trying", I want to risk!
Setting up actions and triggers and using tokens, it is possible to create an efficient method that inform by email the admin, after anonymous user inserts a new comment awaiting approval. Besides it notifies the anonymous of the approval of one's message and any replies, if has left email, as highlighted in the form, overriding the standard strings of Drupal.
Here it is a simple list with the operations that I use to upgrade new release of installed modules and Drupal itself, at the moment only 7 major release, i.e. from 7.x to 7.y where y>x. As far as I know this little guide is sufficient for Altervista.org domains and even for other ones.