Change Sysman Password in OEM repository

Recently I come across the issue when sysman password was changed as it was expired based on password policy.

We have changed the password for sysman user in database using the following command .

alter user sysmand identified by new_password;

then we check the status of OMS and it failed with following error , which is genuine.

[oracle@exadata-an-ora-oem middleware]$ emctl status oms
Oracle Enterprise Manager Cloud Control 13c Release 1
Copyright (c) 1996, 2015 Oracle Corporation.  All rights reserved.
WebTier is Up
Oracle Management Server is not functioning because of the following reason:
Connection to the repository failed. Verify that the repository connection information provided is correct.
Check EM Server log file for details: /u01/app/oracle/gc_inst/user_projects/domains/GCDomain/servers/EMGC_OMS1/logs/EMGC_OMS1.out
JVMD Engine is Down
BI Publisher Server is Down



Error message above itself is explanatory  what the issue is with OMS.  Even if you haven't changed the sysman password itself and you come across this issue, you can easily figure out OMS is not able to connect to repository and so something wrong with either database/listener/ or password.

i checked database was running, so was listener, so we pretty much knew the it was database for sure.

Fix:
update the new password in repository.

emctl config oms -list_repos_details

You have two option.

Option1: if you don't know the old sysman password.

[oracle@oemserver middleware]$ emctl config oms -change_repos_pwd -use_sys_pwd -sys_pwd sys_user_password -new_pwd new_password_4_sysman

Oracle Enterprise Manager Cloud Control 13c Release 1
Copyright (c) 1996, 2015 Oracle Corporation.  All rights reserved.

Changing passwords in backend ...
Passwords changed in backend successfully.
Updating repository password in Credential Store...
Successfully updated Repository password in Credential Store.
Restart all the OMSs using 'emctl stop oms -all' and 'emctl start oms'.
Successfully changed repository password.

OR

Option2: You know sysman old password

[oracle@oemserver middleware]$ emctl config oms -change_repos_pwd -old_pwd sysmanoldpassword -new_pwd mynewpassword
Oracle Enterprise Manager Cloud Control 13c Release 1
Copyright (c) 1996, 2015 Oracle Corporation.  All rights reserved.

Changing passwords in backend ...
Passwords changed in backend successfully.
Updating repository password in Credential Store...
Successfully updated Repository password in Credential Store.
Restart all the OMSs using 'emctl stop oms -all' and 'emctl start oms'.
Successfully changed repository password.

Reference :
       emctl config oms -change_repos_pwd [-old_pwd ] [-new_pwd ] [-use_sys_pwd [-sys_pwd ]]
          Note: Steps in changing Enterprise Manager Root (SYSMAN) password are:
                1) Stop all the OMSs using 'emctl stop oms'
                2) Run 'emctl config oms -change_repos_pwd' on one of the OMSs
                3) Restart all the OMSs using 'emctl stop oms -all' and 'emctl start oms'