mysqlのToo many connectionsエラーについて

mysqlはデフォルトで最大接続数が100に設定されている。
それを越えると接続エラーとなる。(以下はcakephpが出したエラー)

2014-07-21 11:06:09 Warning: Warning (2): mysql_connect() [<a href='http://php.net/function.mysql-connect'>function.mysql-connect</a>]: Too many connections in [CORE/cake/libs/model/datasources/dbo/dbo_mysql.php, line 374]
2014-07-21 11:06:09 Warning: Warning (2): mysql_select_db(): supplied argument is not a valid MySQL-Link resource in [CORE/cake/libs/model/datasources/dbo/dbo_mysql.php, line 379]
2014-07-21 11:06:09 Warning: Warning (2): mysql_query(): supplied argument is not a valid MySQL-Link resource in [CORE/cake/libs/model/datasources/dbo/dbo_mysql.php, line 411]
2014-07-21 11:06:09 Warning: Warning (2): mysql_get_server_info(): supplied argument is not a valid MySQL-Link resource in [CORE/cake/libs/model/datasources/dbo/dbo_mysql.php, line 387]

確認方法

mysql> show global variables like '%max_connection%';
+-----------------+-------+
| Variable_name   | Value |
+-----------------+-------+
| max_connections | 100   |
+-----------------+-------+
1 row in set (0.01 sec)

変更方法

vi /etc/my.cnf

[mysqld]
max_connections=200