Hello! It seems the issue is with dpkg not making the new config files available using the correct name:
# apt install mariadb-plugin-provider-lz4 Setting up mariadb-server (1:10.11.4-1) ... Stopping MariaDB database server: mariadbd. Starting MariaDB database server: mariadbd . . . . . Running '/etc/init.d/mariadb start' failed with error log: 230611 20:15:15 mysqld_safe Starting mariadbd daemon with databases from /var/lib/mysql 2023-06-11 20:15:15 0 [Note] Starting MariaDB 10.11.4-MariaDB-1 source revision as process 4570 2023-06-11 20:15:15 0 [ERROR] mariadbd: InnoDB: compression algorithm lz4 (2) is not available. Please, load the corresponding provider plugin. 2023-06-11 20:15:15 0 [ERROR] Plugin 'InnoDB' init function returned error. 2023-06-11 20:15:15 0 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed. 2023-06-11 20:15:15 0 [Note] Plugin 'FEEDBACK' is disabled. 2023-06-11 20:15:15 0 [ERROR] Unknown/unsupported storage engine: InnoDB 2023-06-11 20:15:15 0 [ERROR] Aborting # ls -la /usr/lib/mysql/plugin/provider_lz4.so -rw-r--r-- 1 root root 14192 Jun 4 18:22 /usr/lib/mysql/plugin/provider_lz4.so # find /etc/mysql/mariadb.conf.d /etc/mysql/mariadb.conf.d/50-client.cnf /etc/mysql/mariadb.conf.d/50-mysql-clients.cnf /etc/mysql/mariadb.conf.d/60-galera.cnf /etc/mysql/mariadb.conf.d/50-mysqld_safe.cnf /etc/mysql/mariadb.conf.d/innodb-lz-compression.cnf /etc/mysql/mariadb.conf.d/provider_bzip2.cnf.dpkg-new /etc/mysql/mariadb.conf.d/provider_lz4.cnf.dpkg-new /etc/mysql/mariadb.conf.d/provider_lzma.cnf.dpkg-new /etc/mysql/mariadb.conf.d/provider_lzo.cnf.dpkg-new /etc/mysql/mariadb.conf.d/provider_snappy.cnf.dpkg-new /etc/mysql/mariadb.conf.d/50-server.cnf # cat /etc/mysql/mariadb.conf.d/provider_lz4.cnf.dpkg-new [server] plugin_load_add=provider_lz4 provider_lz4=force_plus_permanent # cp -a /etc/mysql/mariadb.conf.d/provider_lz4.cnf.dpkg-new /etc/mysql/mariadb.conf.d/provider_lz4.cnf # apt install mariadb-plugin-provider-lz4 mariadb-plugin-provider-lz4 is already the newest version (1:10.11.4-1). Setting up mariadb-server (1:10.11.4-1) ... Stopping MariaDB database server: mariadbd. Starting MariaDB database server: mariadbd. Setting up mariadb-plugin-provider-lz4 (1:10.11.4-1) ... Setting up mariadb-server-10.5 (1:10.11.4-1) ... Processing triggers for mariadb-server (1:10.11.4-1) ... Stopping MariaDB database server: mariadbdERROR 2002 (HY000): Can't connect to local server through socket '/run/mysqld/mysqld.sock' (2) Starting MariaDB database server: mariadbd. # find /etc/mysql/mariadb.conf.d /etc/mysql/mariadb.conf.d /etc/mysql/mariadb.conf.d/50-client.cnf /etc/mysql/mariadb.conf.d/50-mysql-clients.cnf /etc/mysql/mariadb.conf.d/60-galera.cnf /etc/mysql/mariadb.conf.d/50-mysqld_safe.cnf /etc/mysql/mariadb.conf.d/innodb-lz-compression.cnf /etc/mysql/mariadb.conf.d/50-server.cnf /etc/mysql/mariadb.conf.d/provider_lz4.cnf /etc/mysql/mariadb.conf.d/provider_bzip2.cnf /etc/mysql/mariadb.conf.d/provider_lzma.cnf /etc/mysql/mariadb.conf.d/provider_lzo.cnf /etc/mysql/mariadb.conf.d/provider_snappy.cnf The are renamed from *.cnf.dpkg-new to *.cnf only after the installation completes. Perhaps the solution involves adjusting the time when the restart/reload is triggered and somehow force it to happen as late as possible, to ensure the 'Setting up mariadb-plugin-provider-lz4' has happened before server restarts (https://salsa.debian.org/mariadb-team/mariadb-server/-/blob/debian/latest/debian/rules#L239-243). I added a test case for this in https://salsa.debian.org/otto/mariadb-server/-/commits/bugfix/1037327-upgrades-need-provider-plugin-lz and it fails (as expected) in https://salsa.debian.org/otto/mariadb-server/-/jobs/4297516 but if we come up with a solution, at least we have now a test to validate it.
