Change PHP version and PHP settings of your domain
Sometimes it is necessary to change the PHP settings for your web hosting, e.g. to install or update an application. You can define the PHP setting per domain as well as subdomains.
With the new webhostings you can change the PHP version directly in your webhosting control panel. Log in to your my.green.ch account and switch to the Web & Mail Control Panel.
Select the menu Domains (1) . You will get an overview of all domains and subdomains. Under Actions, click on PHP Settings (2) for the wanted sub/domain.
In the selection you can choose the PHP version (3) as well as switch on or off different options.
Finally click on Save Changes (4) to apply the new settings. It may take a few minutes until the new settings are active.
The following tips do not only apply to PHP version changes. They can also be applied in general to customizations (e.g. software update, new plugin, etc).
Testing "Before" and "After
We recommend you to test the website before and after you have changed the PHP settings. This way you can easily see if something has changed in the display or suddenly doesn't work anymore. Does the contact form still work? Can new posts be created, edited and deleted in the forum? Does the image upload still work?
It is best to make the change in a period with few visitors; if your website really goes "offline" directly, not many visitors are affected. Invest the few minutes to test. That way you won't be surprised if something suddenly stops working. Keep an eye on the website in the following days as well. This way, you should also check if your website is still working properly at a time when it has a lot of visitors.
If you don't want to make a "blind" change, check the requirements of the vendor/developer.
Check the requirements for your web application or plugins. You can often find the requirements on the developer's website. Google for the web application in combination with "Requirement" (e.g. Wordpress Requirements) and you will most likely get the right result.
But be careful! Specially with PHP-versions mostly "PHP 5.6 or higher" is given. However, this is no guarantee that recently released PHP versions are already compatible. If you do not find this information from the developer, it helps to search in forums or google for the plugin in combination with the function (e.g. Wordpress YoastSEO with PHP 8.1).
If the desired information is not available, you can still test by activating the new PHP version and, if necessary, reset it again.
Test-/ and productive environment
For very important and complex websites it may be useful to create an identical copy of your website for testing. Afterwards test the changes on the test environment. This way, in the worst case, only the test environment goes "offline" and not the productive website for your visitors. If the changes on the test environment were successful and you then make the changes on the productive environment, test whether everything really works there as well.
If you only change the PHP version in the control panel, a separate backup of the data is not necessary. Only another version is used to which you can switch back. Nothing will be changed on the files or databases at this time.
Does your CMS (e.g. Wordpress) want to make fundamental changes to files (e.g. in the source code) or databases by means of an update? In this case, a backup to which you can switch back to in an emergency makes perfect sense.