Change sysman password Oracle Enterprise Manager

Change directory to OMS_HOME/bin

cd /ssd/oracle/Middleware_1/bin

Stop OMS service

./emctl stop oms

Change sysman password with emctl command

./emctl config oms -change_repos_pwd -use_sys_pwd -new_pwd
./emctl config oms -change_repos_pwd -use_sys_pwd

if we do not provide sys password and new password option then password will be prompted as below.

Stop oms services and start OMS

./emctl stop oms -all

./emctl start oms

Now we can login with new password.