apt update is not working on Plesk server with Ubuntu or Debian after installing PageSpeed Apache: The repository ‘http://dl.google.com/linux/mod-pagespeed/deb/dists/stable/Release.gpg’ is not signed

Symptoms

• Plesk is installed on a server with Ubuntu or Debian operating system.

• PageSpeed module for Apache was installed in Extensions > My Extensions > Google PageSpeed Insights > Open > Install PageSpeed Apache Module.

• The command apt update fails with the error:

  # apt update
  ……….
  Reading package lists… Done
  E: The repository ‘http://dl.google.com/linux/mod-pagespeed/deb stable Release’ is not signed.
  N: Updating from such a repository can’t be done securely, and is therefore disabled by default.
  N: See apt-secure(8) manpage for repository creation and user configuration details.

  Or:

  Installation of Plesk updates fails with the error:

  PLESK_INFO: Failed to update Plesk. To solve this problem, you can send the update log to Plesk support

• The following error can be found in the log file /var/log/plesk/install/autoinstaller3.log:

  Err:10 http://dl.google.com/linux/mod-pagespeed/deb stable Release.gpg
   The following signatures were invalid: KEYEXPIRED 1555048520 KEYEXPIRED 1555048520 KEYEXPIRED 1555048520 KEYEXPIRED 1555048520
   Reading package lists...
   W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used.
   GPG error: http://dl.google.com/linux/mod-pagespeed/deb stable Release: The following signatures were invalid: KEYEXPIRED 1555048520 KEYEXPIRED 1555048520 KEYEXPIRED 1555048520 KEYEXPIRED 1555048520
   W: Failed to fetch http://dl.google.com/linux/mod-pagespeed/deb/dists/stable/Release.gpg
   The following signatures were invalid: KEYEXPIRED 1555048520 KEYEXPIRED 1555048520 KEYEXPIRED 1555048520 KEYEXPIRED 1555048520

• Tools & Settings > Updates and Upgrades > Update Components hangs with the following error:

  PLESK_ERROR: The apg-get failed with the following message:
  Reading package lists…
  Building dependency tree…
  Reading state information…

Cause

The repository which holds packages of PageSpeed module for Apache is incorrectly signed on the side of the repository maintainer – Google.

The bug EXTCERT-2164 was created to handle this issue in the Plesk extension Google PageSpeed Insights. This bug was fixed in the version 2.1.1 of the extension.

Resolution

Update the extension to the latest version.

Note: in case Pagespeed repository was enabled manually, the following steps may be required to disable the misconfigured repository:

1. Connect to the server via SSH.

2. Find the repository configuration file, e.g.:

   # grep -ir pagespeed /etc/apt*
   /etc/apt/sources.list.d/mod-pagespeed.list:deb http://dl.google.com/linux/mod-pagespeed/deb/ stable main

3. Remove the repository configuration file found during the previous step:

   # mv /etc/apt/sources.list.d/mod-pagespeed.list ~/

4. Update APT indexes:

   # apt update