First we need to just clarify how PHP version numbers work. PHP uses a numbering system called semantic versioning. This means that each release has a version number that consists of three parts; the major version, the minor and the patch revision number.
- Upgrades between patch revisions (ie 7.4.11 and 7.4.12) as very unlikely to cause problems as the changes between revisions are normally just bug fixes.
- An upgrade between minor revisions (ie 7.3.1 and 7.4.1) can often be undertaken without any issue although there may be some warnings or notices that didn't appear before the upgrade once you've undertaken it. These would normally only be visible on a development copy of a website where error checking is enabled. There are not normally breaking changes between minor version number changes, however it can't be guaranteed so you should definitely do some research before upgrading and ideally do it on a test copy of the website first.
- An upgreade between major versions (ie 7.4.23 and 8.0.1) should be undertaken with much more caution as breaking changes are more likely. Any problems that arise may be very minor and take just a few minutes to resolve or it may require some real troubleshooting and assistance from others. For this reason it is absolutely vital to test your website running on the new version of PHP.
Clearly making an upgrade between minor or major versions of PHP should be tested before going live on your web server.
If you have no programming experience and / or don't know how to make a backup of your website
then this process is not for you. You will likely need to now call upon a PHP developer to help you. If you need help finding someone see our growing database of PHP developers
What are the best approaches to making a copy of my website?
- If you have experience configuring and making websites ideally you would set up a hidden copy of the website. Naturally you would host it on the same hosting as your live site for a fair test and you would then configure just the copy of the website to run on the newer version of PHP (via a control panel or possibly some script such as .htaccess). This assumes that your ISP supports multiple configurations of PHP as well as a current version.
- If you know that you are going to have to transfer to either a different posting solution of your existing ISP or to a new ISP altogether in order to get a more recent version of PHP then you can take this opportunity to migrate the website to the new hosting and then test before the change goes live. Nearly all web hosting allows you to preview a website so that you can review it before it has its domain pointing to it. You would therefore use this temporary url as a way of checking that the site runs fine on the newer PHP version and when happy update the DNS of your domain to point to the new hosting.
REMEMBER: If you are not comfortable following the above steps don't risk breaking your website! Call upon a web developer with experience
in websites built in PHP.