I suggest to upgrade Matomo
from 4.15.1 to 5.0.3
Matomo 5 + stongly reccomend PHP 8+
https://matomo.org/faq/on-premise/matomo-requirements/
I tried to move Matomo from mod_php to PHP FPM.
Without success.
I created the PHP pool
/etc/wmit-infrastructure/servers/intreccio/conf/php/8.1/pool.d/it.wikimedia.matomo.conf
created user and group
matomo-wikimediait
modified apache vhost
/etc/apache2/sites-available/it-wikimedia-matomo-ssl.conf
but when tried i get
root@intreccio:/etc/wmit-infrastructure# systemctl status php8.1-fpm.service
● php8.1-fpm.service - The PHP 8.1 FastCGI Process Manager
Loaded: loaded (/lib/systemd/system/php8.1-fpm.service; enabled; vendor preset: enabled)
Active: failed (Result: exit-code) since Fri 2024-03-08 10:57:36 UTC; 8min ago
Docs: man:php-fpm8.1(8)
Process: 4268 ExecStart=/usr/sbin/php-fpm8.1 --nodaemonize --fpm-config /etc/php/8.1/fpm/php-fpm.conf (code=exited, status=78)
Process: 4269 ExecStopPost=/usr/lib/php/php-fpm-socket-helper remove /run/php/php-fpm.sock /etc/php/8.1/fpm/pool.d/www.conf 81 (code=exited, status=0/SUCCESS)
Main PID: 4268 (code=exited, status=78)
Mar 08 10:57:36 intreccio.wikimedia.it systemd[1]: Starting The PHP 8.1 FastCGI Process Manager...
Mar 08 10:57:36 intreccio.wikimedia.it php-fpm8.1[4268]: [08-Mar-2024 10:57:36] ERROR: [pool it.wikimedia.www] unable to set listen address as it's already used in another pool 'it.wikimedia.matomo'
Mar 08 10:57:36 intreccio.wikimedia.it php-fpm8.1[4268]: [08-Mar-2024 10:57:36] ERROR: failed to post process the configuration
Mar 08 10:57:36 intreccio.wikimedia.it php-fpm8.1[4268]: [08-Mar-2024 10:57:36] ERROR: FPM initialization failed
Mar 08 10:57:36 intreccio.wikimedia.it systemd[1]: php8.1-fpm.service: Main process exited, code=exited, status=78/CONFIG
Mar 08 10:57:36 intreccio.wikimedia.it systemd[1]: php8.1-fpm.service: Failed with result 'exit-code'.
Mar 08 10:57:36 intreccio.wikimedia.it systemd[1]: Failed to start The PHP 8.1 FastCGI Process Manager.@valerio.bozzolan could you plaease check ?
Bonus topic
Thare are missing tag containers in matomo.
They works but are not available for editing.