nginx: unknown directive pagespeed after Plesk 18.0.79

If nginx stopped starting or reloading after a Plesk update, with a message like unknown directive "pagespeed", this page explains what changed and how to get nginx running again.

What changed

Plesk’s release notes record the change in two steps:

• Plesk Obsidian 18.0.77 (31 March 2026) announced that support for the ngx_pagespeed.so module would be deprecated and removed from the sw-nginx package.
• Plesk Obsidian 18.0.79 (23 June 2026) removed the module from nginx. Plesk’s announcement gives the reason as a security vulnerability in the PSOL library (libwebp).

Sources: the Plesk Obsidian change log and the 18.0.79 announcement.

The update removes the module but not your configuration. Any pagespeed directive left in an nginx configuration now refers to a module that is no longer loaded, and nginx refuses a configuration that contains a directive it does not know. That is why the whole server fails to start or reload, not only the sites that used PageSpeed.

Get nginx running again

1. Find every place that still refers to the module:

   sudo grep -rn "pagespeed" /etc/nginx

   Directory layout differs between installations, and a panel may keep per-domain configuration elsewhere. Widen the search to wherever your configuration lives. Per-domain directives are often visible only in the panel, so check there too.

2. Remove or comment out what you find:

   • every pagespeed ...; directive, not only pagespeed on;. Directives such as pagespeed FileCachePath fail the same way.
   • any load_module line that points at a missing module file.

   Remove them where they were entered. A panel can generate parts of the web server configuration, so make the change in the panel’s per-domain nginx settings rather than in generated files, and in any custom include file you created yourself. See Plesk’s own documentation for how your version handles custom nginx directives.

3. Test the configuration, then reload nginx:

   sudo nginx -t
   sudo systemctl reload nginx

   If your host has more than one nginx, run nginx -t with the binary your server actually uses.

Your sites serve normally again, without PageSpeed optimization.

Options going forward

These are independent choices. None of them is required to get nginx running.

Do without it. Leave the lines out. Pages are served unoptimized.

Use mod_pagespeed with Apache. The maintained mod_pagespeed has an Apache module. Our documentation covers stock Apache on Debian, Ubuntu and the RHEL family. It does not cover Apache as installed and managed by Plesk, and we have not tested it there, so we cannot say whether it works in that setup. If you try it, treat it as unverified and test on a staging domain first. We would like to hear how it goes through the contact page.

Run nginx with our module outside Plesk’s nginx. The nginx module loads into the nginx that your distribution ships. For nginx.org’s stable nginx there is a separate package, nginx-module-pagespeed-nginxorg, built for one nginx version at a time (currently 1.30.6), for amd64 on Debian 13, Ubuntu 24.04 and Enterprise Linux 9. It cannot be installed together with the distribution package. The module does not load into a different nginx build, and we have not documented or tested it for the sw-nginx package. We make no claim that it works there. Running our module means running one of those supported nginx builds yourself, outside the panel’s nginx, and you own that setup and its upgrades.

If you are replacing another ngx_pagespeed build, see Migrate from ngx_pagespeed: your pagespeed directives carry over to the maintained module, except seven deprecated names: 2.8.2 refuses them, so delete them before you install it. The next release accepts them with a deprecation warning.

Plesk is a trademark of its owner. This page is not affiliated with or endorsed by Plesk.