Tips for Using WordPress on a Gandi Web Hosting¶
Here is some practical information that will help you make the most of your WordPress installation at Gandi.
500 Internal Server Error¶
This error is generally due to a problem with the code of your website. It usually appears as an all-white page. With WordPress, it is usually caused by a WordPress plugin or theme.
In order to determine what is causing the problem, go to your web hosting’s control panel, and examine the contents of the PHP error log: www-error.log
You will see errors like:
PHP Fatal error: Class 'WP_Customize_Section' not found in /srv/data/web/vhosts/www.exemple.tld/htdocs/wp-content/themes/easy-store/inc/customizer/es-custom-classes.php on line 341
Consequently, in order to regain access to your website, you will need to deactivate the theme or plugin that is causing the problem from the WordPress admin.
If, however, the WordPress admin is not available, you can still log into your web hosting using an sFTP client. Then, rename the plugin or theme directory that is causing the problem in order to deactivate it. These will be in the /htdocs/wp-content/themes or /htdocs/wp-content/plugins directories.
If you activated https on your site, but there is no green padlock appearing in your browser’s address bar, it is possible that some elements of your website, such as images, are still being loaded using the http protocol.
To confirm this:
Use the Web Developer tool of your browser (pressing the F12 key for Firefox and Chrome will bring this up.)
A new window will open to display the tool.
Click “Console” and look at the results to find where the problem comes from.
Once you have found the links causing the problem, edit them so they use https and not http.
You can use a special plugin, SSL Insecure Content Fixer, to help, if you have a lot of elements needing to be fixed.
We provide a test URL with every web hosting. If you started working on your website at that address, but then want to switch the site to its definitive address later, there is a plug-in that you can use, called “Duplicator” to help you do this.
The role of this plugin is to update the address of your website in the WordPress admin and database.
As a security measure, WordPress recommends the addition of the following rewrite line in the .htaccess file located in your WordPress’ root directory (this would be in the htdocs directory).
RewriteRule ^xmlrpc\.php$ "http\:\/\/0\.0\.0\.0\/" [R=301,L]
By doing this, all connection attempts targeting this file will be redirected, and so xmlrpc pingback attacks will be averted.
You can find more information about this at: https://www.trustwave.com/Resources/SpiderLabs-Blog/WordPress-XML-RPC-PingBack-Vulnerability-Analysis/
If you suspect you are being hit by such an attack, check your Apache access.log file and look for a large number of access requests to this file, in this form:
POST /xmlrpc.php HTTP/1.1" 200 56775 "-" "-"
Gandi’s Web Hosting already makes use of a special cache system to increase performance. Consequently we recommend that you avoid using a WordPress cache plugin, as it would be counterproductive, and would use up resources of your web hosting for no reason.
How to Install wp-cli¶
You don’t have the rights in the Web Hosting system’s directories, but you can use alias instead.
At first, you need your SSH console to be activated, and then connect to it.
Then, run the following commands :
$ cd /srv/data/home $ wget https://raw.githubusercontent.com/wp-cli/builds/gh-pages/phar/wp-cli.phar $ chmod +x wp-cli.phar $ echo "alias wp='/srv/data/home/wp-cli.phar'" >> /srv/data/etc/bash/bashrc
Afterwards, press CTRL-D (to leave current session), then press ENTER (to open a new session). And test it:
$ wp --info
Site Blocked in Maintenance Mode¶
Sometimes after a plugin update fails your site may be blocked with the error “Temporary unavailability due to maintenance. Please come back in a moment.”. This is caused when your website fails to exit maintenance mode when the plugin update fails. To fix this error and disable maintenance mode, follow these steps:
Connect to your web hosting with your usual sFTP software.
Go to the Vhost, at the root of your Wordpress site.
Find and delete the “.maintenance” file. If you don’t see the file you may need to change the options of your FTP software to display hidden