安裝mysql後，系統中會有多個my.cnf檔案。

使用 locate my.cnf 命令可以列出所有的my.cnf檔案

➜ locate my.cnf
/etc/my.cnf
/usr/local/mysql/mysql-test/include/default_my.cnf
/usr/local/mysql/mysql-test/suite/federated/my.cnf
/usr/local/mysql/mysql-test/suite/ndb/my.cnf
/usr/local/mysql/mysql-test/suite/ndb_big/my.cnf
/usr/local/mysql/mysql-test/suite/ndb_binlog/my.cnf
/usr/local/mysql/mysql-test/suite/ndb_ddl/my.cnf
/usr/local/mysql/mysql-test/suite/ndb_memcache/my.cnf
/usr/local/mysql/mysql-test/suite/ndb_rpl/my.cnf
/usr/local/mysql/mysql-test/suite/ndb_team/my.cnf
/usr/local/mysql/mysql-test/suite/ndbcluster/my.cnf
/usr/local/mysql/mysql-test/suite/rpl/my.cnf
/usr/local/mysql/mysql-test/suite/rpl/extension/bhs/my.cnf
/usr/local/mysql/mysql-test/suite/rpl_ndb/my.cnf
 

1. 檢視是否指定目錄下的my.cnf

➜ ps aux | grep mysql | grep 'my.cnf'

命令輸出結果中的--defaults-file，就是mysql啟動載入的配置檔案。如果沒有輸入結果，則表示沒有設定使用指定目錄的my.cnf。

2. 檢視mysql預設讀取的my.cn

➜ mysql --help|grep 'my.cnf'

                      order of preference, my.cnf, $MYSQL_TCP_PORT,
/etc/mysql/my.cnf /etc/my.cnf ~/.my.cnf

命令mysql --help|grep 'my.cnf'