I have try stop before change port
1. stop
[root@Jbosstest ~]# service mysqld stop
Stopping mysqld: [ OK ]
[root@Jbosstest ~]#
2. change port
[root@Jbosstest log]# cat /etc/my.cnf
# For advice on how to change settings please see
#
http://dev.mysql.com/doc/refman/5.7/en/server-configuration-defaults.html
[mysqld]
#
# Remove leading # and set to the amount of RAM for the most important data
# cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%.
# innodb_buffer_pool_size = 128M
#
# Remove leading # to turn on a very important data integrity option: logging
# changes to the binary log between backups.
# log_bin
#
# Remove leading # to set options mainly useful for reporting servers.
# The server defaults are faster for transactions and fast SELECTs.
# Adjust sizes as needed, experiment to find the optimal values.
# join_buffer_size = 128M
# sort_buffer_size = 2M
# read_rnd_buffer_size = 2M
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
#port = 3360
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
port=65514
[root@Jbosstest log]#
3. Start
[root@Jbosstest log]# service mysqld start
MySQL Daemon failed to start.
Starting mysqld: [FAILED]
[root@Jbosstest log]#