title: What is the configuration file of MariaDB?
body: <p>I'm using stand-alone database on Debian, and I'm new to MariaDB. 
  In MySQL, I used to deal with only one <code>my.cnf</code> which contained all relevant parameters that I needed. </p>
  
  <p>Here, in MariaDB 10, there are dozens of them:</p>
  
  <pre><code>/etc/mysql# tree
  .
  ├── conf.d
  │   ├── mysql.cnf
  │   └── mysqldump.cnf
  ├── debian.cnf
  ├── debian-start
  ├── mariadb.cnf
  ├── mariadb.conf.d
  │   ├── 50-client.cnf
  │   ├── 50-mysql-clients.cnf
  │   ├── 50-mysqld_safe.cnf
  │   └── 50-server.cnf
  ├── my.cnf -&gt; /etc/alternatives/my.cnf
  └── my.cnf.fallback
  </code></pre>
  
  <p>I need to modify parameters like <code>max_connections</code>, <code>innodb_buffer_pool_size</code> and <code>long_query_time</code> to register slow queries. I added them to <code>my.cnf</code> but then the server refused to restart. </p>
  
  <p>So I'm wondering what file should I modify?</p>