> ## Knowledge Base Index
> Fetch the complete knowledge base index at: https://help.faaaster.io/sitemap.xml
> Use this file to discover available pages before exploring further.
> Pure-Markdown content can be obtained by appending a '.md' suffix to the content URLs listed in the sitemap (without the trailing slash).

# What are debug mode and read-only mode for on Faaaster?

**Debug mode** displays PHP and WordPress errors on the site's pages; **read-only mode** locks the files to prevent any change to the code. The first is set from the **Server** tab, **Advanced** section, the second from the **Security** tab.

## Debug mode

According to the interface: "Activate the debug mode of WordPress and PHP."

> **Beware: errors will be displayed on your site pages**, so your visitors can see them. Only turn it on for the duration of a diagnosis, and turn it off right afterwards.

It's located in the **Server** tab, **Advanced** section.

## Read-only mode

According to the interface: "Lock the files for writing to prevent any modification of the code. The `/wp-content/uploads` directory will remain open for writes."

It's located in the **Security** tab, **Server security** section, **Read only** row.

In practice: with read-only mode on, WordPress can no longer install or update plugins or themes. Media uploads, however, still work.

On a large site, the switch can take a while. If the interface shows "We couldn't confirm this change yet", wait: the switch updates by itself with your site's actual state. Check it before trying the action again.

## Which one to use when?

- **A problem to diagnose** → debug mode, temporarily.
- **A production site you want to freeze** → read-only mode.

![The Advanced section of the Server tab, where debug mode is set.](https://storage.crisp.chat/users/helpdesk/website/-/9/d/2/d/9d2d3e0b7134b800/act-serveur-debug-en_1pxdxdz.png)