diff --git a/mysql/README.md b/mysql/README.md
index f39c6f84..4c813a15 100644
--- a/mysql/README.md
+++ b/mysql/README.md
@@ -20,16 +20,16 @@ Tasks are extracted in several files, included in `tasks/main.yml` :
 
 * `mysql_variant` : install Oracle's MySQL or MariaDB (default: `oracle`) [Debian 8 only];
 * `mysql_replace_root_with_mysqladmin`: switch from `root` to `mysqladmin` user or not ;
-* `mysql_bind_address` : (default: `127.0.0.1`) ;
 * `mysql_thread_cache_size`: number of threads for the cache ;
 * `mysql_innodb_buffer_pool_size`: amount of RAM dedicated to InnoDB ;
-* `mysql_max_connections`: maximum number of simultaneous connections (default: `250`) ;
-* `mysql_max_connect_errors`: number of permitted successive interrupted connection requests before a host gets blocked (default: `10`) ;
-* `mysql_table_cache`: (default: `64`) ;
-* `mysql_tmp_table_size`: (default: `128M`) ;
-* `mysql_max_heap_table_size`: (default: `128M`) ;
-* `mysql_query_cache_limit`: (default: `8M`) ;
-* `mysql_query_cache_size`: (default: `256M`) ;
+* `mysql_bind_address` : (default: `Null`, default evolinux config is then used) ;
+* `mysql_max_connections`: maximum number of simultaneous connections (default: `Null`, default evolinux config is then used) ;
+* `mysql_max_connect_errors`: number of permitted successive interrupted connection requests before a host gets blocked (default: `Null`, default evolinux config is then used) ;
+* `mysql_table_cache`: (default: `Null`, default evolinux config is then used) ;
+* `mysql_tmp_table_size`: (default: `Null`, default evolinux config is then used) ;
+* `mysql_max_heap_table_size`: (default: `Null`, default evolinux config is then used) ;
+* `mysql_query_cache_limit`: (default: `Null`, default evolinux config is then used) ;
+* `mysql_query_cache_size`: (default: `Null`, default evolinux config is then used) ;
 * `mysql_custom_datadir`: custom datadir.
 * `mysql_custom_tmpdir`: custom tmpdir.
 * `general_alert_email`: email address to send various alert messages (default: `root@localhost`).
diff --git a/mysql/defaults/main.yml b/mysql/defaults/main.yml
index 1b83fc86..d93f7270 100644
--- a/mysql/defaults/main.yml
+++ b/mysql/defaults/main.yml
@@ -14,16 +14,20 @@ mysql_replace_root_with_mysqladmin: True
 mysql_custom_datadir: ''
 mysql_custom_tmpdir: ''
 
-mysql_bind_address: '127.0.0.1'
 mysql_thread_cache_size: '{{ ansible_processor_cores }}'
 mysql_innodb_buffer_pool_size: '{{ (ansible_memtotal_mb * 0.3) | int }}M'
-mysql_max_connections: '250'
-mysql_max_connect_errors: '10'
-mysql_table_cache: '64'
-mysql_tmp_table_size: '128M'
-mysql_max_heap_table_size: '128M'
-mysql_query_cache_limit: '8M'
-mysql_query_cache_size: '256M'
+
+# If these variables are changed to non-Null values,
+# they will be added in the zzz-evolinux-custom.cnf file.
+# Otherwise, the value from de the z-evolinux-defaults.cnf file will preveil.
+mysql_bind_address: Null
+mysql_max_connections: Null
+mysql_max_connect_errors: Null
+mysql_table_cache: Null
+mysql_tmp_table_size: Null
+mysql_max_heap_table_size: Null
+mysql_query_cache_limit: Null
+mysql_query_cache_size: Null
 
 
 mysql_cron_optimize: True
diff --git a/mysql/templates/evolinux-custom.cnf.j2 b/mysql/templates/evolinux-custom.cnf.j2
index 0fff23b9..796a1429 100644
--- a/mysql/templates/evolinux-custom.cnf.j2
+++ b/mysql/templates/evolinux-custom.cnf.j2
@@ -1,12 +1,31 @@
 [mysqld]
+{% if mysql_bind_address %}
 bind-address = {{ mysql_bind_address }}
+{% endif %}
+{% if mysql_thread_cache_size %}
 thread_cache_size = {{ mysql_thread_cache_size }}
+{% endif %}
+{% if mysql_innodb_buffer_pool_size %}
 innodb_buffer_pool_size = {{ mysql_innodb_buffer_pool_size }}
+{% endif %}
+{% if mysql_max_connections %}
 max_connections = {{ mysql_max_connections }}
+{% endif %}
+{% if mysql_max_connect_errors %}
 max_connect_errors = {{ mysql_max_connect_errors }}
+{% endif %}
+{% if mysql_table_cache %}
 table_cache = {{ mysql_table_cache }}
+{% endif %}
+{% if mysql_tmp_table_size %}
 tmp_table_size = {{ mysql_tmp_table_size }}
+{% endif %}
+{% if mysql_max_heap_table_size %}
 max_heap_table_size = {{ mysql_max_heap_table_size }}
+{% endif %}
+{% if mysql_query_cache_limit %}
 query_cache_limit = {{ mysql_query_cache_limit }}
+{% endif %}
+{% if mysql_query_cache_limit %}
 query_cache_size = {{ mysql_query_cache_size }}
-
+{% endif %}