How Reset the SYSMAN password in OEM 12/13c

-- Stop all the OMS:

$OMS_HOME/bin/emctl stop oms

-- Modify the SYSMAN password:

$OMS_HOME/bin/emctl config oms -change_repos_pwd -use_sys_pwd -sys_pwd <sys pwd> -new_pwd <new sysman pwd>

* I got some errors on this command.

In this case I started the OMS in admin only mode and the command worked correctly.

$OMS_HOME/bin/emctl stop oms -admin_only

-- Re-start all the OMS:

$OMS_HOME/bin/emctl stop oms -all

$OMS_HOME/bin/emctl start oms