howto? coexists two differents mysql versions on same server

[Victor Diez]

Hello,

We have a working MySQL 4.1.22 (production) box (over EL5 i686) and we just add a couple new filesystems and did a MySQL 5.1.52 binaries/catalog fresh installation on them with its own config files and enviroment but sharing OS owner with 4.1

The thing is the 4.1 box was configured with standart /etc/my.cnf and now we need both instances coexists for a short period of time (while we do the export/import for data), but we are facing troubles with --defaults-file= invoking mysqld_safe on 5.1; it seems it's ignored due the existence of /etc/my.cnf and we are not sure if is it safe to move it or remove it since the service from 4.1 can't be stop it (it's a production system).

is there a way to start the recently 5.1 box without affect the 4.1 service?

4.1: my.cnf (currently at /etc/my.cnf)
[client]
socket=/Mysql/logs/mysql.sock
port=3306

[mysqld]
port=3306
datadir=/Mysql/Data
tmpdir=/Mysql/logs
socket=/Mysql/logs/mysql.sock
pid-file=/Mysql/logs/mysql.pid
log-error=/Mysql/logs/mysqld.log
log-bin=/Mysql/logs/binlog

default-table-type=innodb
max_connections=400
max_allowed_packet=25M
innodb_log_file_size=20M

innodb_data_home_dir = /Mysql/Data
innodb_data_file_path = ibdata1:50M:autoextend
#innodb_data_file_path=ibdata1:32768M;ibdata2:2048M:autoextend
innodb_log_group_home_dir = /Mysql/Data
innodb_buffer_pool_size = 100M
innodb_additional_mem_pool_size = 5M
# Set .._log_file_size to 25 % of buffer pool size
innodb_log_file_size = 20M
innodb_log_buffer_size = 5M

5.1: my.cnf
[mysqld]
user=mysql
port=4306
basedir=/Mysqlecat/mysql
datadir=/MysqlData
socket=/Mysqlecat/logs/mysql.sock
pid-file=/Mysqlecat/logs/mysqld.pid
log-error=/Mysqlecat/logs/error_mysql.log
slow-query_log=ON
slow-query_log-file=/Mysqlecat/logs/slowq.log
#log=/Mysqlecat/logs/general.log

default-storage_engine=InnoDB
max_allowed_packet=100M
max_connections=400

innodb_file_per_table
innodb_data_home_dir=/MysqlData
innodb_data_file_path=ibdata1:100M:autoextend
innodb_buffer_pool_size = 500M
innodb_log_file_size = 100M
innodb_log_buffer_size = 20M