mysqli_connect(): (HY000/2002): No such file or directory

hi . problem this : Database_Exception [ 2 ]: mysqli_connect(): (HY000/2002): No such file or directory so, mariandb do not started. problem that this : Process: 30038 ExecStart=/usr/sbin/mysqld $MYSQLD_OPTS $_WSREP_NEW_CLUSTER $_WSREP_START_POSITION (code=killed, signal=ABRT) Thanks please check the problem :(